Dr Rupy: Sarah, you have looked at meal timing in your research, our responses to sugar, satiation. With all that in mind, I want to ask you a simple question. What do you eat for breakfast and why, to stay healthy?
Dr Sarah Berry: So my breakfast varies day to day. And the reason it varies is because I'm a great believer that food's there to be enjoyed as well as to be healthy. So I generally pick the kind of breakfast that I feel like at the time. So if I'm feeling that I fancy something quite healthy, then I will go for a yogurt with lots of kind of, you know, homemade granola, berries, nuts, etc. If I'm hungover, nothing beats a good old bacon sarnie on really unhealthy white bread with lashings of butter. And often at the weekend, because I'm cooking breakfast for my family, my kids love pancakes with loads of Nutella. So, you know, again, it's that whole social side of things. I love sitting down with the kids, having the pancakes with them on a Saturday.
Dr Rupy: This is
Dr Sarah Berry: So different foods for different reasons.
Dr Rupy: Definitely, yeah. And you know what, I think it's really important to never forget the enjoyment of food beyond its sort of health effects. If we were looking purely at the health effects, how would you create a breakfast that is in line with all the things that you're across with with your research?
Dr Sarah Berry: Yeah, so firstly, I'd love to pick up on that point that you said that I'm a great believer if a food is too healthy to be enjoyed, it's just not healthy at all. So that's always in my mind when I'm thinking about any kind of meal, whether it's breakfast, lunch, snacks or dinner. If I was to design the perfect breakfast, which obviously is going to be different for everyone. Firstly, it's thinking also, are you hungry for breakfast? Don't just eat breakfast out of habit. Listen to your hunger signals. Some people, you know, are breakfast skippers, they're either just not hungry in the morning. So firstly, do you even want breakfast before you even start thinking about what's in the breakfast. Then I would say, make sure that you're having a breakfast that's you enjoy, that's going to make you feel full for long enough so that you can be productive in the morning, that's not going to give you big sugar peaks and crashes, so kind of sugar dips that we know will make you go on to eat more, and want to eat a lot more soon as well. So these are the kind of breakfasts that will be generally high in healthy, high quality proteins, healthy fats, plenty of fibre. So I think my kind of golden breakfast that I would suggest is a breakfast that has maybe some Greek yogurt, some kefir, so you've got some of your fermented food, you've got some of the great properties of dairy coming in from the Greek yogurt as well. Nuts, nuts are like powerhouses for food and I'd love to discuss nuts in more detail because I've spent many years researching nuts. Seeds, you know, maybe some dried fruits, different berries, etc. And then you're getting like a complete breakfast that's giving you fibre, protein, good quality fats, but more importantly, hopefully it's tasty and it's giving you a diversity as well because we know it's really important to have a diversity, a diversity of different fibres, a diversity of different plant-based foods as well.
Dr Rupy: Totally. And you mentioned whether you even feel like breakfast or not. Do you routinely skip breakfast every now and then or are you the kind of person that needs their breakfast first thing in the morning?
Dr Sarah Berry: So I don't eat it immediately that I wake up. Like my son needs breakfast before he's barely opened his eyes, otherwise he gets seriously hangry. Um, and yeah, my daughter could go till midday nearly without eating breakfast. And that just shows the huge variability in what, you know, how we naturally have different kind of chronotypes or different times of the day that we want to eat based on our biology. I'm in the middle between my daughter and my son. So I don't like to eat immediately upon waking. I would generally have breakfast once I've dropped the kids to school. So I generally will come back to the house, take some breakfast up and have some breakfast while I'm flicking through emails, which really you shouldn't do because we know the evidence shows if you're distracted while eating, you overeat, but. And so it's normally a couple of hours after I've woken up. That's what suits me.
Dr Rupy: It's interesting there because I can see you wrestling in your mind about like things that you know are quote unquote unhealthy or not advised, but we still do them. Like I still like eat al desko sometimes, you know, in front of my computer whilst I'm waffing down my lunch or breakfast or whatever. And I know it's unhealthy. And some people, for some people, that can spiral into shame and negativity. And for other people, we seem to be able to wrestle with it. I wonder your thoughts on those because you're across so much, it can get a bit overwhelming.
Dr Sarah Berry: Yeah. So I've worked as a nutritional scientist for over 20 years as an academic, you know, in the depths of research. Quite often as a nutritional scientist, we think of the underpinning science, the mechanisms, we often don't think of the application. So it's really funny because until the work that I've been doing over the last six years with Zoe, which has been very much thinking about how we apply the science into people's everyday lives, I'd actually really not thought much about my own diet and how it impacts my health. And it's only the last few years that I've become more aware of, you know, little things like, you know, oh, if I slow down how fast I'm eating the food, or if I try not to snack late at night, or if I just do this simple swap, it can actually have a big impact on my health. Now, some choices I make and I'll be like, okay, actually, that will have a reasonable impact on my health and I will still enjoy it as much. With the knowledge I have, I'm lucky that I can decide which choices will have a big impact but minimal impact on my health but minimal kind of effect on my pleasure. And I think this is where it's really challenging for people out there that there's so much misinformation. There's so much information as well about things that I think are just kind of, you know, trimming around the edges that people say, oh, there's this great new diet or there's this, you know, great new wonder food, which or superfood, which is nonsense anyway, the whole term superfood. But actually the size effect of how much it impacts your health is tiny. And I think that's the greatest thing of having worked in this area for so many years. I know what's going to actually have a bigger effect and what's just, you know, yeah, trimming around the edges.
Dr Rupy: Yeah, totally. And I think that's sort of macro picture of this is going to yield 80% of the benefits to my diet. And this, you know, perhaps it is isn't the healthiest, but I'm consuming so little of it that the effect on my well-being is going to be negligible. And it's sort of giving people those health reflexes so they can decipher that on their own day-to-day. And you mentioned you've got two kids, is that right?
Dr Sarah Berry: Yeah.
Dr Rupy: When you're a parent, it can also be quite overwhelming. So you're not only looking after your own diet, although you mentioned that your husband is the main cook in the household. But when you're like making pancakes with chocolate spreads and all that kind of stuff, and you know what's in it, and you're across, you know, what ultra processed foods can do to kids' health and development and all the rest of it. Again, how do you wrestle with that? Because that can get quite overwhelming, particularly for parents who may not even come from a nutrition background, so they can't decipher what the big macro picture is for their children.
Dr Sarah Berry: I'll be really honest with you that I do worry about what I feed my kids. I could feed them a lot healthier diets, but I think I represent a lot of the mums that are out there or representative of a lot of the mums out there. You know, I have a really demanding job or two jobs, my King's job as an academic, my Zoe job as well. And to juggle two jobs and my husband works long hours and to also deliver day after day healthy food, healthy snacks for the kids, it's a challenge. And you know, there are lots of strategies we can put into place like bulk cooking, etc, etc. But look, I'm, I live in the real world where I have this idea of every week, I'm going to feed the kids better. I'm going to bulk cook all the evening meals. I'm going to do healthy packed lunches. There's different barriers to that. There's one, the fact that my kids don't like certain things. But there is the reality we live such busy lives. We have stepped away from a lot of home cooking, which isn't a good thing. And we live in this food landscape that we're just not evolved to handle all these ultra processed foods. And so I think as a parent, yes, I do have that battle a lot more about what I'm feeding my kids versus me. But I'm also pragmatic that I don't sweat the small stuff. And so for example, on a Saturday having a Nutella pancake, it's not going to kill them. You know, I'm not giving it them for, you know, continuously all day every day. And I think it's also really important that we enable our kids to appreciate, you know, all different types of foods and understand some foods are healthier than others, but it doesn't mean anything's out of bounds.
Dr Rupy: Yeah, absolutely. And I think that's a really healthy relationship to have with food because we do live in an ultra processed food landscape. And unless you're able to tolerate and navigate that world, it's going to be very difficult for them when they're adults and they have to make those choices themselves. And I really, really appreciate that vulnerability and that honesty actually, because so many people will be listening to this and thinking that's me and I feel guilt and I feel shame when I do. So that I think is, yeah, it's going to be super impactful. Just the fact that you're you're opening up and you're telling us here, it's not all diversity bowls and nuts and yogurt and all this kind of stuff. It's actually real stuff.
Dr Sarah Berry: Come and spend, come and spend the day in my house. Do you know what? Honestly, I go to bed every night sitting on my phone too late doing my emails, doing everything I know I shouldn't be doing. And honestly, the last thing I think before I go to bed is, I've got to feed the kids healthier tomorrow. I've got to stop doing emails late at night. I've got to be more present with the kids after school. Do I do it every day? We're human. I try.
Dr Rupy: Yeah. No, we try. No, it's great. Well, let's let's talk about what things that we can do.
Dr Sarah Berry: I'm painting, I'm painting an awful picture, aren't I? It's my family.
Dr Rupy: You're painting a very realistic picture. And I think it's just like small steps to success. Like there's this um, uh, there's this newsletter that I follow. It's by a guy called George Mack. He's a um, uh, quite a well-known person in the agency field and um, it's got this um, uh, newsletter called, I think it's called 0.1%. It comes out every week. And there's this sort of, I think it this originally came from James Clear, where if you try and improve by 0.5% every single day, it might not seem that much on a day-to-day basis or a week-by-week basis, but over the course of a year or five years, it's going to amount to a massive change. So I think we overestimate what we can do in the short term, we underestimate what we can do in the long term. So maybe it's a case of, you know, trying a different natural chocolate spread at the weekend and just see if they like it. If they don't, great, we'll try something else. Or, you know, adding a few more berries on top of the pancakes when you make them. Like little things that may seem insignificant in the short term, but actually over time, they amount to a lot.
Dr Sarah Berry: Yeah, yeah. I think that's a really good point. And I think, you know, this is why lots of people I think fail when they're trying to improve their diet because they go all out. They're like, right, that's it. Or, you know, I'm not drinking alcohol. I'm not going to have any sweets, sugars, this, this and this. I'm only going to drink plant-based. I mean, come on, you're just setting yourself up for failure. Well, for some people that approach might work. And it's just those really, you can do so many little add-ons that actually build up to have a big, big impact.
Dr Rupy: Totally. Yeah. So
Dr Sarah Berry: Do you know what? This Saturday, I'm going to put some raspberries with those Nutella pancakes.
Dr Rupy: There you go. You can send me a picture of that.
Dr Sarah Berry: I'll be thinking of you this Saturday morning.
Dr Rupy: I love that. Um, let's talk a bit about, uh, traditional sort of breakfast that everyone has believed to be healthy. And okay, we'll put the judgment to one side and I don't want people to think, oh, you know, you've just talked about being realistic and and now we're talking about, um, the golden breakfast as you put it. Uh, oats, are they a healthy breakfast? Are are we changing our opinion on oats because of perhaps, you know, people's responses to to sugars and and the starches?
Dr Sarah Berry: So it depends. And I'm afraid I'm really sorry, but I'm probably going to say this far too many times throughout the podcast, but it depends. It depends of what would you be eating instead? Now, if you're eating it instead of craves, which my son loves, unfortunately. And I don't know if you do you I've probably don't know what craves are.
Dr Rupy: I've heard of craves because I've passed them. Mitch is nodding his head behind the camera. I've heard of craves because I've passed it in the cereal aisle, but I don't spend much time in the cereal aisle, honestly, unless I'm buying oats and they're organic and jumbo and all the rest of it. But no, tell me about craves.
Dr Sarah Berry: Okay, don't eat craves. Um, but so it depends and this this applies for everything in nutrition. Instead of what? What would you be eating instead of that? So oats, you know, instead of craves, whoa, they're great. Could you have an even healthier breakfast? Probably, yes. It also depends on the type of oats you're getting. And this is what's really, really important. I think we become so fixated with um, single aspects related to foods. Like oats, that's it, they're bad because they increase your glucose. Well, they have loads of other properties that are great for us. It's not all just about one kind of effect that a food has, for example, on your glucose. But we also know that food is so much more than what appears on the back of pack labeling. And we know this from our own research. So we did a study where we fed people whole large oats, and then we also fed people exactly the same oats, but we ground them down. Okay? So back of pack labeling would be identical, identical calories, identical nutrients. Okay? But the way that we process the ground oats, which is how many of the oats are now sold in the supermarket, is that we metabolize them really quickly. So what I mean by that is that you have a really big increase very rapidly in circulating blood glucose. So that's like the sugar in your blood. Compared to the whole large, very traditional oats that you can still buy in the supermarkets. So these are ones that are about two millimeter size if you want to get your rulers out. Um, and so what we found is if we feed the same people one day these big, you know, old traditional oats and then another day the kind of oats that often are sold, that you get about a 30 to 40% difference in this kind of glucose, this blood sugar response. And that's just because of the way that they're ground. So that's a great example of if you could eat those oats in that kind of traditional, those large oats, the steel cut kind of rolled oats, then you're not going, you shouldn't, I don't think be worrying too much about, you know, having a big sugar peak. And that's only one aspect of how oats impact our health. But it's when you're you're fiddling around with how they were meant to be eaten, that's when they become a problem. There's also ways that you can combine foods in order to make them even healthier. And I think this is again, oats is a great example. So oats are quite high in carbohydrate. They will cause an increase in circulating glucose. You know, add something that's also got additional fibre or additional protein or additional fat to it. Add, you know, full fat milk if that's what what you like, or add, you know, Greek yogurt to it, um, you know, add something that maybe has some protein like, you know, uh, nut butter, that sort of thing to it. And then you're you're, you know, boosting its health properties as well.
Dr Rupy: When I think about using oats, because I I love oats, um, but I rarely have just oatmeal on its own, even if it's steel cut or jumbo or rolled and all the rest of it. Um, I usually add things like shelled hemp seeds, a nut butter, um, some pumpkin seeds, like it's quite a high protein, high fat breakfast, and it kind of breaks up that carbohydrate. And for that, I even though I don't regularly wear a continuous glucose monitor, I feel intuitively more satiated. I'm less likely to snack mid-morning. And for me personally, that works really well. And just so that that idea of like combining foods and the food matrix to sort of, um, mitigate against any sugar rises is is an important aspect, I think. So I and I and I appreciate the it depends. And I'm sure we're going to hear that after every single question I'm going to ask you here.
Dr Sarah Berry: I'll try not to. But I think that's a great example of the power of combining foods. You know, the protein, the fibre slows down the rate that your stomach empties. So naturally slows down the rate at which the the sugars are appearing in your bloodstream. And so that's a way again, you're kind of offsetting a little bit some of the the potential downsides of oats. But I would never, you know, I I would never consider for most people oats to be a bad food unless you're having these really heavily processed oats. And I think though, we need to think about also what works for one person doesn't necessarily work for another person. And so it's interesting that whenever I used to have porridge, I'd feel so hungry, you know, maybe two, three hours later, and I'd feel quite shaky and a bit a bit weird. And one of the biggest kind of, uh, sort of light bulb moments for me in all of my nutrition career is when I actually wore a continuous glucose monitor. Um, and what that showed me is when I was having certain, uh, breakfasts that were very high in carbohydrate, such as, um, the these kind of very processed oats, but also like white bread, etc. I was getting a glucose dip, so a blood sugar dip two to four hours after having that for breakfast. And when I was wearing the monitor, I could actually feel at that point in time, oh, I was feeling a bit hot and sweaty. I was feeling like brain foggy. And then I'd go back and have a look and I could see the dip. And we've actually done some work with our Zoe predict study where we found that about 25% of people are what we call dippers. Um, and so these are people that typically have a dip after a carbohydrate meal, regardless of whether it's oats or bread or whatever. Um, and so about two to four hours after having a meal that's got carbohydrates in it, they'll have this dip. So this is about one in four people. And then we compared those to people that don't have dips. So we looked at big dippers versus little dippers. And what we found is people that were big dippers, they went on to eat their next meal half an hour before the little dippers. We found that they ate 320 calories more over the whole day than people that didn't have the dips, that they ate about 100 calories more at their next meal. They also said they felt less alert, they had less energy and generally felt more hungry throughout the day. And but other people didn't have dips. So that just shows again that, you know, oats might cause dips for some people, it might be perfectly fine for other people.
Dr Rupy: Totally. Yeah. I want to put a pin in the oat thing for a second actually, because I want to come back to that. But on the subject of little dippers and big dippers, what about people who had a high carbohydrate meal in the evening? Did you again notice dips and would that lead to increased calorie consumption over the course of 24 hours? Because obviously you're going straight to bed afterwards. And B, did that affect sleep quality? I'm sure there's something in there that you've perhaps looked at already.
Dr Sarah Berry: It's a good question. We haven't actually looked at dipping at night. Generally, we've looked at it in the morning because we've wanted to look at people when they all coming in the kind of similar state, i.e. a faster state. We do know from our research and other published research that eating late in the evening is not great for our health. This is quite a new area of research that's emerging. It's one of those areas I'd very much say watch this space, but based on the strength of the evidence, I would say that trying to avoid eating after 9 o'clock if you can, particularly snacking. And we know from our own research that 30% of people snack after 9 o'clock.
Dr Rupy: 30%? I'm definitely in that category.
Dr Sarah Berry: 50% snack after 6 in the evening. But what we do know is how your body processes food later in the day is different to how you process it in the morning. So what our research does show that if you have a high carb meal in the morning versus the afternoon, you have a lower overall glycemic response. So an overall lower blood sugar response in the morning compared to the afternoon. So you could have two identical meals. If you were to have, what's your favorite snack?
Dr Rupy: My favorite snack, you're going to Okay, give me a carbohydrate, give me a carbohydrate food that you love.
Dr Sarah Berry: A carbohydrate food that I love. Um, I like, I do like crackers, but these are seeded crackers, so I guess that's not quite.
Dr Rupy: That's fine. We'll go, we'll go with that. We'll go with that.
Dr Sarah Berry: They're delicious crackers. I just want to hide in like buckwheat, nigella seeds. We've got them on the app. They're, yeah, you can find the recipe. If anyone's wondering what crackers does Dr. Rupy eat.
Dr Rupy: Um, and then you're to have exactly the same delicious crackers later in the day. Um, on average, what we would find is that your blood glucose response would be worse to those crackers later in the day. So you're metabolizing it differently, you're processing it differently. There's also some really fascinating research showing that your hunger and fullness signals to those crackers would be different. So those crackers when you have them in the morning, your delicious crackers, would make you feel reasonably full, would make you feel not very hungry. When you have those delicious crackers later in the day, um, I'm sorry, I'm taking the mickey out of your delicious crackers.
Dr Sarah Berry: It's all right, but they are delicious.
Dr Rupy: It's because they're not Jacobs with slathers of butter on. I love a Jacobs cracker.
Dr Sarah Berry: You can, you can imagine the Jacobs with butter, that's a lot easier for you.
Dr Rupy: Um, when you're having them later in the day, even though you're having exactly the same ones that you had in the morning, they will not make you feel as full. You will feel a little bit more hungry. So your fullness and your hunger signals also start to decline later in the day, as well as how you process the food. And then the last thing that we know as well, this isn't from our evidence, this is from some great studies that have come out recently, that show that if you eat later in the day, you actually wake up feeling more hungry. And so let's say you were to have your typical meal and finish, sorry, your typical day's eating, and you were to start, let's say at like 8:00 in the morning and finish at, I don't know, let's say 6:00 in the evening. And then the next day you'd have exactly the same food, but you were to shift it, let's say to start at 12:00 and then do the same eating window, which means finishing at 10:00 at night, if I've done the maths correctly. That even though you'll have eaten the same, when you have that day when you eat later, you're going to wake up feeling more hungry, even though you've eaten later.
Dr Sarah Berry: Wow.
Dr Rupy: So you're metabolizing the food worse by eating late at night, that you are feeling less full from the food when you eat late at night, and you're feeling more hungry in the morning. So using that, and I just want to caveat here that other things being equal and depending on someone's, you know, individual circumstances, if somebody was thinking about an intermittent fasting regime, like a 16/8 or whatever, would it be on average better to have your eating window that is earlier? So include breakfast. So instead of skipping breakfast, actually include breakfast and finish up earlier in the day, let's say 6:00 p.m. if your bedtime is 9:00 or 10:00.
Dr Sarah Berry: So on average, yes, the evidence would point that early time restricted eating as we call it. So starting earlier in the day and finishing earlier in the day is better for your overall metabolic health. So a lot of the risk factors related to type two diabetes, cardiovascular disease, so inflammation, your blood lipids like cholesterol, your glucose control. Um, in terms of your weight, so if people are practicing time restricted eating for weight control, there doesn't seem to be as big a difference. So it seems to be effective regardless. Any time restricted eating, I think the evidence, the strength of the evidence shows that it's effective in improving both your health and improving your weight. I think the important thing to say is just do what works for you.
Dr Rupy: Yeah, totally. It's all about convenience because some people, you know, don't have the opportunity to eat earlier or don't have the opportunity to eat an earlier dinner. So, you know, like when I was doing night shift work and stuff, like it's impossible to put all these things into practice. So just if anyone's listening, just take that with a grain of salt.
Dr Sarah Berry: And I think that's really important to say that a lot of people do work night shifts. A lot of people it's outside of their control. And you know, we've often talked on some of our podcasts about the importance of not eating late at night, the importance of eating in line with your body clock. So, you know, every cell in our our body has a little clock. It's not possible for everyone. And you know, I think it's really important to recognize that we know that it's not possible for everyone. But I also think on the subject of time restricted eating, it's really important to highlight that you don't have to go to extremes. Like some of the the schedules out there that you see is like eat within a four or six hour window. My gosh, what kind of life do these people live? I'm fine if it works for you. So I'm not. But I want to be going out with my friends in the evening and having a drink or, you know, and a meal and totally. And you know, to eat in that window, it, like I said, it might work for some, but it's really restrictive. And we actually conducted a study called the big if study, the big intermittent fasting study. And this was about a year and a half ago. And this was a a Zoe study where we recruited 150,000 people. And what we said to them is, look, there's this great evidence to show time restricted eating works. But actually it's based on evidence coming from really tightly controlled, kind of randomized control trials. So they're clinical style studies in in very tightly controlled conditions. We live noisy lives. We don't live in a metabolic unit. Does it actually matter in the way that we live our lives? And this is really important for all of the evidence that we see out there. There's so many fantastic studies that come out showing, oh, this is good for you, that's good for you. Okay, fine. But we live really noisy lives. Does it actually still have an impact? What's the size effect we often talk about in science. So we said to all these people that signed up, have your normal diet for a week. Now, uh, try time restricted eating. Don't go to extremes. Just see if you can eat within a 10-hour window. So that means if you have your breakfast at 8:00, finishing um, oh gosh, I'm terrible with the maths today.
Dr Rupy: At 6:00.
Dr Sarah Berry: At 6:00, thank you. If you have your breakfast at 10:00, it's finishing at 8:00 p.m. Um, which a lot of people can do. Carry on doing everything else that you would normally do. See what happens. And it was amazing because people reported that on average they had better mood, they had better energy, they had less hunger, and they also lost weight. And for most people, they were only reducing their eating window as we call it. So the time period in which they were eating by about one and a half hours. Now, the longer they reduced it, yes, maybe the bigger impact it was having on some of these outcomes. But people were still seeing a really great impact from just reducing it by an hour and a half. And so the the take home from that is, yes, it even in the way we live our noisy lives, it still helps. But you don't need to go to extremes.
Dr Rupy: Totally. Yeah. And I think also it depends on the health goals or um, the intentions of somebody who wants to do intermittent fasting. Is it to, you know, reduce their cravings and snacking? Is it to improve their sleep? Is it to lose weight? For certain people, intermittent fasting whereby they don't consume enough calories, they don't consume enough protein, that may have a detrimental effect. And actually, that's something I noticed when I was doing slightly more extreme. I wasn't going as extreme as four hours, but I was going, you know, six, six to seven hours. It was hard, really hard. Um, but not because I couldn't do it, just because I couldn't get enough of the good stuff into my six, seven hour window. So I think again, it really depends on like, you know, whether someone is looking to lose weight or not, or weight maintenance or improve sleep, etc, etc. Um, but it's fascinating, absolutely fascinating. I want to take the pin out of the, uh, the oats because I want to go back to that. Sorry, I just got to remember.
Dr Sarah Berry: I'm sending us in circles, aren't I? I get excited by so many different areas as we're talking.
Dr Rupy: That's your role. My role is to just keep you on track. That's it. I this I I love it. So, um, we're talking about oats and the, uh, way in which we consume them. So you've got the jumbo two millimeter oats with your ruler. Um, does that extend to other products, uh, on the market shelves? And I'm specifically thinking of things that I personally love to eat. So lentil pastas. I love lentil pasta because my my wife is gluten-free, uh, even though she's Italian, so she regards it as a bit of a curse, uh, because she loves pasta, she loves, you know, Italian cooking, obviously. Um, so we use lentil pasta. Some of them are great, some of them are not great. But they have identical, um, nutritional labels. So you've got whole lentils from a packet that are either pre-cooked or raw. And then you've got lentil pasta, which is 100% lentils and a bit of water. Nutritionally, same amount of protein, same amount of carbs. I'm assuming they're going to be drastically different in terms of how we process them based on the way that they are prepared.
Dr Sarah Berry: Yeah. So I've done a little bit of research related to this area, but using chickpeas. So, you know, it's still kind of broadly similar. There's still a lot we don't know related to um, how they're processed and how they impact our health. What we do know is that firstly, any lentils, whether they're in pasta, ground, whatever, are going to be great for you. Okay? So if that's how, you know, how you enable yourself to eat the pasta, but also enable yourself to have lentils, fine, have them. We know that if you break down the cell structure of any plant-based food, how you process it is different. And so, for example, work we've done with chickpeas shows that if you have the chickpeas where they're largely intact, and by that, even mashing, I mean intact, rather than like industrially processed. What we know is that when you metabolize them, you metabolize them slightly differently. So firstly, you metabolize them more slowly. So again, you have this less more kind of blunted blood sugar rise. And we know this from some research that we've published at King's College on this. We also know that where they're absorbed in the gut is slightly different. So when you have the unprocessed, for example, chickpeas, they enter further down into your gut. So they in your small intestine, you have loads of different receptors related to hunger and fullness, for example. I'm kind of oversimplifying it, but I think hopefully to to um, you know, explain why we feel differently after the two different types. With the whole chickpeas, then or or the chickpeas that are only kind of lightly mashed, they enter lower down where you actually have a higher density of receptors related to fullness. So you'll also feel fuller. And again, we've seen this with our own research as well. So also if so it's affecting our blood sugar response, but it's also affecting where it's absorbed in the gut and then the different kind of gut signals. So all these different hormones that go back to our brain and say how full we are or how hungry we are. And so that's a great example of how it affects metabolism, but also how we're feeling and our our hunger signals as well. But like you say, they'd be identical in terms of back of pack labeling.
Dr Rupy: And is there um, a difference between the original product itself, right? So if we're comparing oats, whole oats to oat flour, that's going to be different because oats tend to not have as much protein as a lentil or a chickpea, for example. So chickpea is going to have a bit more protein. So is the effect of processing going to be again impacted by the original nutritional values or do we just not have enough research?
Dr Sarah Berry: So it's going to be impacted by the original plant it comes from. And maybe I could use nuts as an example of this because this is something we've done quite quite a bit of research on. So nuts is a great example where actually the way it's processed affects the energy content. So and and this shows the complexity of food, which, you know, is why I think it's it's a mind field out there because every food's so different. So oats are a great example how processing affects how you metabolize it. So that blood sugar response. The chickpeas is a great example of how when you process it, you change where it's absorbed in the gut and therefore hunger signals. Nuts, by processing nuts, you actually change how much energy you absorb. So nuts, um, and it's same applies for seeds. They have cell walls. Okay? So every nut has a millions and millions of cells. Inside of each cell in a nut is where the fat is, the fat soluble nutrients like the vitamin E, for example. Now, these cell walls in nuts are quite rigid. So what happens is is when you chew a nut, so let's say you have a whole almond and you chew the nut, you fracture some of the cell walls. Okay? So you do break by the chewing process some of the cell walls. But the cells are tiny. They're smaller than a grain of sand. So we've done what we call these mastication studies where we get people to chew nuts and then spit them out. On average, when you spit, when you chew a nut, at the point at which you're about to swallow, they're about two millimeters the chunks. So you're only actually breaking a few of the cell walls. Inside that two millimeter chunk, I know it's not a very nice thing to think about, like imagine your mouth with two millimeter chunks of nuts. You've still got hundreds and hundreds of cells that have these really rigid cell walls that have got all of this fat encapsulated. Now, it then enters your stomach, it then where it's broken down a little bit more, it then enters your small intestine where you've got all of these enzymes coming and breaking down the cell walls a little bit. But actually the enzymes aren't strong enough to fully break down the cell wall structure. So what happens is is about 30% of the energy actually just comes out in your poo because you've got these cells that are still intact, these cell walls that are still intact containing all of this fat. So firstly, what's great is that you've got all of this great food for your gut microbiome because it's entering your large intestine, so it's entering that kind of large part of the gut where all of these microbes are happy having a party on on the nut bits that are coming through. But also 30 to 40% of the calories are coming out being excreted. And that's a great and so if you were to have whole nuts where you've got 30% of these calories coming out, or you were to really finely grind these nuts. And I don't mean using a home kind of, you know, blender. I mean like commercial grinding that's really to such a fine powder. Like a marzipan, for example, you know, the kind of texture of that. You're going from having getting 100% of the calories to getting in the natural way they were meant to be having only 60 to 70% of the calories. And that's from a single, yeah, back of pack labeling is identical. So back of pack labeling shows that a portion of of almonds, so 28 grams is a portion, have 170 calories. What research shows is that actually on average, only 128 calories are actually metabolized. But not everyone's average. And I'll tell you what, there's some if I can sidetrack onto this quickly. From this same research that showed that on average, we actually only absorb 128 calories, we saw there's huge variability between individuals. Some people absorb the full 170 calories. And so some people are like super metabolizers. They were getting all 170 calories. Some people only absorbed 60 calories from that portion. That's a difference of 100 calories. Oh no, 110 calories. My maths really are not on on form today. So we're talking about a difference of 110 calories from a portion of nuts between one individual and another. You know, that's crazy. So firstly, there's the whole fact that look, on average, we're not absorbing all, but look at the variability in how we respond to food.
Dr Rupy: Is there any evidence that explains that difference? Is it in their um, in the enzymes that they have in their mouth or their digestive tract or their microbes or anything like that?
Dr Sarah Berry: We don't know yet. That's so interesting. But the point from this is that if you, I would encourage everyone to eat nuts, but let's say you were going on a calorie restricted diet, which also I'd caveat that that isn't the best way to lose weight, but let's say you were wanting to count your calories, would you be wanting to count them based on that back of pack labeling of 170 if you were the person that's only absorbing 60 of the calories? Would we want to give the same advice to that 170 calorie super absorber versus the 60 calorie poor absorber? And I think it's a really good way that I often use with my students at Kings to talk about how the advice we give to one person doesn't necessarily work for another person.
Dr Rupy: Do we know the extremes of those two? Sorry, just to stick on this subject for a second because I find it fascinating. Are is there like a bit of a normal distribution, I like the majority of people that will absorb on average 60 to 70% and at the extremes you've got like a smaller population?
Dr Sarah Berry: Gosh, that's such a good question. And I don't know the answer, um, in terms of giving you exact figures. But you are correct that it's kind of like what is often the case in science, what we call a bell-shaped curve, that lots of people stick around that middle bit. But I would have to go and check the data, but I think that this is more dispersed if I remember correctly.
Dr Rupy: Wow, that's so interesting. And let's play a bit of a game actually, because I know people are going to be screaming at me to ask you this question. Let's use the example of um, chickpeas. Yeah. Um, and let's rank the way in which we would consume chickpeas if other things being equal, we just want you to eat chickpeas, whether it's ground in a flour, in a pasta, in a hummus or whatever. But in terms of getting the most nutritional value from a chickpea, like let's say A is, I know, I'll give you the options and you can put it like in A to D or whatever we've got. So you've got raw chickpeas that are then cooked overnight, similar way and you know, they're edible. You've got canned or jarred chickpeas. You've got chickpeas in a hummus with just like, you know, olive oil, a bit of salt, let's say it's a very nice one from Natura or something like that. Um, and then you've got chickpea flour and what other chickpea pasta, let's say. In terms of getting the most nutritional value, how would you rank those options?
Dr Sarah Berry: Okay, that's a hard one. It's a hard one. It depends what you mean by most nutritional value. Okay, I would put the um, like raw fresh ones and the tins probably the same, assuming that the tin is just in water or whatever. However, that's what initially I was thinking. You said that you had some olive oil with the hummus. Now assuming it's great extra virgin olive oil packed with polyphenols, heart healthy fats. I'm going to rank that the same. So I'm actually putting those even if I'm allowed to.
Dr Rupy: That's a good point. You can, yeah, absolutely. Yeah.
Dr Sarah Berry: Um, and then and also, you know, the olive oil as well as all those polyphenols and fats, you're also, you know, um, modulating how you process it because the fats delaying gastric emptying. So I might actually put that slightly above the others. But it depends what what it depends what other additives and stuff are in there.
Dr Rupy: It depends on the additives. I get it. Let's let's imagine like it's a really, it's one that I've made. It's one that I've used the best extra virgin olive oil I can find.
Dr Sarah Berry: Okay, so let okay, I'm going to put that slightly above the others.
Dr Rupy: Oh, interesting.
Dr Sarah Berry: Because it's about mixing and adding different stuff in. Actually, I'm going to put that above the others. Then I would put the tinned and the fresh together. And then I would put the flour next and then probably the pasta.
Dr Rupy: The pasta at the bottom. Okay, that's good to know. But always with the caveat that, you know, we're not telling people that you shouldn't have the flour and the pasta and stuff. It's really about getting the chickpeas in your diet in in its entirety. But what I'm getting there is actually the food combinations are probably more important than the individual ingredients.
Dr Sarah Berry: Yeah, absolutely. You know, we don't eat, well, rarely do we, we don't eat individual nutrients, which is why a jar of pasta of chickpeas at home. And we don't generally eat in general individual foods. And that's why us when we talk about nutrition, I think everyone tries to have this reductionist view of talking about fat, protein, fibre, carbohydrate, what's better for you? What food is better for you? We don't eat a nutrient on its own. We don't generally eat a food on its own. Let's talk about whole diets. But the chickpea flour is really interesting because we've done a study where we actually put chickpea flour into bread. So we all know that, you know, processed white bread isn't the best for us. It isn't the best for us for a number of reasons, partly because of its glycemic index, so how quickly it increases your circulating blood glucose or or blood sugar. Um, but also because of some of the other properties of of processed white bread. But people like white bread. And so this is where I think we can use processing in a clever way that we have to acknowledge people do want to eat white bread, people are going to buy it. Can we make it healthier? And so we did some research where we actually added chickpea flour into the white bread. We took out some of the white flour and we looked at different levels how it impacted our postprandial glucose responses. So these uh blood sugar responses after eating it, as well as our feeling of fullness and hunger. And if we added in some chickpea flour, took out some of the normal flour to the extent that it didn't affect palatability, so how tasty it was for people. We actually found it significantly reduced the circulating blood glucose, blood sugar, but also made people feel fuller for longer as well.
Dr Rupy: And would you, um, would you, uh, think that's because of the protein and the extra fibre content that's making them feel fuller?
Dr Sarah Berry: So I think it's one, the fibre, the protein, delaying gastric emptying, but also because we know from what I mentioned earlier, even as a flour, we believe it's being digested a bit lower down the gastrointestinal tract. So it's causing more of these fullness signals to go to your brain.
Dr Rupy: That's so interesting. I I really think that and not to take us too much of a side track here, I really think there is something that we can do with current processed foods that are never, I don't think they're going to go away. I think people have acclimatized to them, they like the taste and like like you were saying at the start of this podcast, who doesn't like a a white bread butty with like, you know, bacon and loads of HP.
Dr Sarah Berry: Not every day. Not every day.
Dr Rupy: I don't like HP with it.
Dr Sarah Berry: Oh, you don't like HP with it?
Dr Rupy: No, I like it in my beans. A bit of Heinz beans with HP.
Dr Sarah Berry: Oh, you don't like it with bacon? The saltiness and the tamarind and the sweet.
Dr Rupy: No, I don't like to mess with it. White bread, butter, bacon.
Dr Sarah Berry: Do you like tamarind?
Dr Rupy: Tamarind's quite sour. We use it a lot in like Sri Lankan cooking, Indian cooking, that kind of thing.
Dr Sarah Berry: I don't know, my husband does the cooking.
Dr Rupy: Okay, fine, fine. Ask your husband.
Dr Sarah Berry: So he might put it in the food. I'm very ignorant, aren't I, what I'm eating.
Dr Rupy: Um, no, that's I think there's a lot we can do with processing and like, you know, sneaking things in to increase protein and the the whole whole food ingredients that we can add to processed foods.
Dr Sarah Berry: Absolutely. Like there's this whole area of what's called health by stealth. And the chickpea uh, like powder into bread is a great example. The new pastas and rices that are coming out with pulses. Yeah, you should always eat something in the original state that it was designed to be eaten in, you know, or it was created or evolved to be eaten in. But you're you're right to acknowledge that the reality is is that we're not going to suddenly stop eating ultra processed food. So we need to think about ways that firstly, we can reduce our intake. I don't mean eliminate, but reduce our intake. But secondly, how can we actually use it maybe to our advantage? And that's where the health by stealth, I think, and adding in some of these ways of processing food to actually make it healthier could be, you know, a winner given our current food landscape.
Dr Rupy: Totally. And I think, you know, a lot of people will be frustrated to see that now we have an ultra processed food landscape. And for decades, we've been told that original whole foods like eggs, uh, other dairy products, butter, whole milk were unhealthy, quote unquote. And now we've been told, oh, they're not as unhealthy as they were, depends on how you combine them and all that kind of stuff. Maybe we can talk a bit about how our opinions on these whole food products are changing, particularly as egg, I think is a great way to start your day and, you know, it's got those all these different nutrients in that can be satiating and actually lead to overall less calorie consumption in the day and actually a preference for, yeah, more sort of satiating foods.
Dr Sarah Berry: Oh, can I go back to the start and change my breakfast? I forgot about eggs. Talking about yogurt and granola. If I can, I'm going to add that in.
Dr Rupy: Yeah, add it in.
Dr Sarah Berry: Let's, I think eggs, I'm, I'm eggs, avocado, that's amazing for breakfast.
Dr Rupy: Yeah, absolutely. Okay, cool. We can add that in now.
Dr Sarah Berry: So, my thoughts are that it's important to understand that nutrition science is evolving rapidly and eggs is a great example of this. Dairy is a great example, which you also alluded to. That, um, we've in the past thought about the health effects of food in too much of a simplistic way, i.e. the nutrients that are in the food, you know, so the fat, the fibre, the carbohydrate, the cholesterol. Eggs is a great example of this where we've thought, okay, there's quite a lot of cholesterol in eggs. We know that cholesterol increases our risk of heart disease. That's it. Eggs are bad for us. And so there's a period in time, um, where we were therefore discouraged from consuming eggs because we believed it would increase our risk of cardiovascular disease because it we believed that the cholesterol in it would therefore lead to heart disease. What we know is that dietary cholesterol, i.e. the cholesterol that you eat, so the cholesterol that you're getting from eggs, is actually quite different from the cholesterol that your body makes, that your liver produces. So what we know is that certain types of saturated fat cause our liver to produce cholesterol. We know that some of this cholesterol is bad for us, which we call LDL cholesterol. But when we eat cholesterol, so from cholesterol rich foods, which isn't just eggs, we know that some, you know, seafood, for example, and other foods have cholesterol, actually, it only has a tiny, tiny, tiny impact on the level of cholesterol that's circulating in our blood. And it's only if you get above a certain level of dietary cholesterol, that actually it increases the level of cholesterol that circulates in your blood. And it's the cholesterol that circulates in your blood that's bad for you, not what you're putting into your mouth. And so having two eggs a day, I think, you know, maybe not every day of the week, but having up to seven eggs a week, I think the the evidence shows that it wouldn't have any unfavorable effect on your health.
Dr Rupy: Okay. That's it's really good to know. And I think, um, the one to two eggs every day or two eggs every now and then during the week is good general advice. When it comes to specific, um, circumstances for people that might, let's say, already have a raised LDL cholesterol, which is a marker in their blood, or, um, a newer marker that's getting a little bit more popular now, so your apolipoprotein B, for example, that seems to be more, um, tightly associated with cardiovascular disease risk. For those people, even though the effect is minimal, is it worth taking out of their diet any source of cholesterol or are the benefits of having that as a, you know, satiating breakfast far outweighing the potential downsides?
Dr Sarah Berry: That's a good question and I don't know the answer to that given it's kind of that risk health benefit. Based on what evidence I do know, I would suggest that for people that have, uh, high cholesterol, assuming as long as it's not excessive, I still think having a few eggs here and there during the week is okay. Is the culprit more so the specific types of saturated fat in our diet? And I specifically said specific types of saturated fat because I think there's discussion about where we get our saturated fats and which ones are a little bit more, um, even cardio protective if not neutral versus, um, damaging.
Dr Rupy: Yeah, so, um, this is actually part of what I did my PhD on. So we could be here all day, but I'm going to keep it, I'm going to keep it quite succinct as possible. So you're right, there's two things that we need to think about. One is the type of saturated fat. So we know that saturated fat consists of different types. So there's palmitic acid, stearic acid, myristic acid, etc. And we also know that the different types impact our cholesterol differently. So we know for example, one type which is called stearic acid has a neutral effect on our cholesterol. It has a neutral effect on the bad cholesterol, our LDL cholesterol, it has a neutral effect on HDL, our good cholesterol. We know that palmitic acid and this is found in a lot of tropical oils as well as also in dairy, actually can have an unfavorable effect. So it increases our bad cholesterol, our LDL. And then there's other fatty acids as well that we know that particularly are found in dairy as well that increase our LDL, our bad cholesterol. But where it gets really interesting is we know that in addition to how the individual fats, the individual saturated fats impact our cholesterol, the food matrix in which they're delivered in modulates it. And so this is why I always say, and I know I've said it already a few times today, we can't think of food as the nutrient. We have to think about the food vehicle it's delivered in. And dairy is a great example. So what we know is, and we don't fully understand why, we know that fermented dairy, despite having some of these types of saturated fats that are bad for us that raise our LDL, our bad cholesterol, they don't actually have a negative impact on our cholesterol. They don't actually increase our risk of cardiovascular disease. And so the advice that had been given for many years, you've got high cholesterol or you're at increased risk of cardiovascular disease, don't eat any dairy. We know that doesn't hold true for all dairy. So what we do know is for butter, which isn't fermented, yes, it does raise your cholesterol. It raises your bad cholesterol. Now, having a little bit of butter on your toast each morning isn't going to be, you know, a big deal. But if you have the kind of diet where you're cooking everything with butter, you're using lashings of butter, yes, that's not great. But what we know is that fermented dairy, so that's the cheese and the yogurts, that even though they have the same fats, the same types of saturated fats as butter, they seem to have a neutral effect in terms of our risk for cardiovascular disease and in terms of our cholesterol. If anything, because of all the other great properties, you know, the calcium and all the other great nutrients that are in there, they seem to actually be associated with a reduction in risk.
Dr Rupy: Yeah, yeah. So I think again, it's the point of the food matrix, how you're consuming certain fats rather than this is a bad fat and this is a good fat.
Dr Sarah Berry: Yeah, absolutely. And I think this is why we need to be really careful looking at those back of pack labelings because again, you could look at butter, you could look at cheese, they're almost, not quite, but almost identical back of pack labeling. But their health effects are hugely different. Takes us back to the oats, the the almonds, the chickpeas. Try and think of food as food. Try and think of it as in meals, as in your whole diet. Try not to think of it as nutrients. Except fibre.
Dr Rupy: Except fibre.
Dr Sarah Berry: Sorry, I have to caveat that. Everyone should eat more fibre. Focus on that as a nutrient.
Dr Rupy: I'm confusing things now, aren't I?
Dr Sarah Berry: No, no, no, but it's a very confusing subject. And I I'm glad we're talking about the nuances of this because, um, there is a lot of, uh, dogmatic, uh, behavior, a lot of dogmatic beliefs out there. Um, that, you know, everything is wrong, ergo, you should eat as much butter as you like and as many eggs as you like and all that kind of stuff. But the reality is that it depends very much on like, you know, how we all respond.
Dr Rupy: I've said it, my favorite word. It depends.
Dr Sarah Berry: So, um, one thing that I've definitely noticed, um, two things, and I'm conscious not to take us down a complete rabbit hole here. People who are purposely adding, uh, specific types of saturated fats to their diet. So MCT oil being added to certain foods that's rich in, I think, I think it's caprylic acid from coconut, which is where they've, um, extracted it from, um, that tropical oil to to put in MCT like, um, uh, bottles, I think you can get them. Um, and then also, I wanted your perspective on people who eat quite a high saturated fat diet. So let's say a carnivore or a keto diet, and they do their bloods and they don't actually have that bad looking blood work. So LDL cholesterol is fine, apoB is fine, triglycerides are low. How do we explain that through the lens of nutrition given everything we know about the damaging effects of these potential fats?
Dr Sarah Berry: So I think a lot of that evidence comes from what we call N of one studies. So studies where, you know, you've got these Instagram influencers saying, hey, I'm just eating red meat all day and this has happened to my bloods. Well, I'd like to see what else they're eating is all I would say. And so maybe they are eating lean red meat. Maybe they're not having all the fat on it, but maybe all the rest of their diet is actually incredibly healthy. So I don't actually pay much attention to some of these N of one Instagrammers, you know, like these seed oil haters and some of the, I call it nutribollocks, but you might have to cut that out. So or nutrinonsense.
Dr Rupy: I did a radio interview once where I said it's all nutribollocks. And I got asked to, I, no, they did an apology at the end because it was live. And they apologized for my language.
Dr Sarah Berry: But there's so much nutrinonsense out there. It's crazy. I don't know without knowing what other specific things, but you know, it's complicated, it's nuanced and this is where it's really difficult as a nutrition scientist because the public perception is that we're changing our minds constantly. Well, firstly, the evidence is evolving. Secondly, we all respond differently. You know, we see that with our our Zoe predict studies. But thirdly, because it's so complicated, but because we want to give simple messages, sometimes we simplify it down, I think too much and that causes the confusion. And that's why I think actually giving more food-based advice rather than the nutrient-based advice would be the answer. So I haven't fully answered that question.
Dr Rupy: No, that's fine. I I I agree with you regarding the N of one point. I think it's really hard to, uh, determine exactly what other, uh, activities an individual is doing that can lead to, you know, uh, blood work changes and all the rest of it. But there is something curious going on with certain people who are able to tolerate whopping amounts of saturated fat more than the average would be able to tolerate and consume without harmonious blood work.
Dr Sarah Berry: Well, we know there are certain, uh, genetic phenotypes, so certain, um, uh, genetic differences in people actually related to saturated fats. So it's a great example. So we know that for a particular, um, uh, protein that's involved in, uh, how we process and circulate, um, our blood, we know that some people have a slightly different genetic makeup for that. And therefore can tolerate saturated fat, uh, better. But, you know, not everyone has that.
Dr Rupy: Yeah. And there's a whole bunch of like, you know, snips that are becoming popular for, you know, companies to test like apoE4 and, um, FADS2 and all all these like, you know, weird and wonderful names. And I think they give part of the picture, but not the full picture. So it can explain certain elements, but maybe not the whole thing.
Dr Sarah Berry: Yeah, so this is something we've focused on a lot with our predict studies is looking at what explains the huge variability in how we respond to food. And we see from our own studies, and this is in thousands, hundreds of thousands of people, we see that there's about a 20-fold difference in how one person responds to a food versus another person responds to a food. We see that there are certain foods and certain nutrients, dare I say it, that just are bad for everyone. We see that there are certain foods and certain nutrients like fibre that are just good for everyone. But then there's a whole area in the middle that we all respond a little bit differently to. And when we try and look at what's explaining this variability, what's explaining all of this noise, we see that some of it's due to genetics, but actually it's not that much. Okay? So some of it's due to genetics. Some of it's due to other factors about us. So our age, our sex, our menopause status, for example, are we pre or post menopause. Um, uh, our microbiome, um, you know, other kind of circulating metabolites. Some of it's due to how we eat our food. So this takes us back to what we talked about earlier, like the time of day that we're eating our food, our meal ordering, our eating rate, you know, um, uh, time of day. And, you know, some of it's due to other lifestyle factors, like how much sleep we've had, when we're exercising, etc. So when we think of the role of genetics and how one person responds differently, we need to put it in the context of not just who we are in our genetics, but all these other factors as well.
Dr Rupy: Yeah, totally.
Dr Sarah Berry: But we do respond, we are all different. And that's why I think we've got to be so careful when, you know, we are on social media and we see, you know, I don't know, some or as a nearly 50 year old, I see people like Jennifer Lopez and I'm like, oh my gosh, what's she doing to look like that? And but what works for her isn't going to work for me.
Dr Rupy: Sarah, as you just mentioned that you're nearly 50, people are going to be thinking exactly the same thing about you now. They're going to be putting you next to JLo.
Dr Sarah Berry: I'm not in a bikini. Or, you know, and you you you see that actually that worked for them, but and you see all these people like, oh, she did this, that's going to work for me. It's like, no, everything's, you know, and also, you know, how painful what has she had to go through to do that? I'm not prepared to do that.
Dr Rupy: It doesn't seem like you need to. Um, you mentioned it a couple of times now, the way in which we eat food, I think is super important. So the sequence of nutrients, the order in which we eat foods, the eating rate, and like, how would you even measure that? Um, maybe we can talk about how that actually affects the absorption of the calories in a typical meal and maybe some practical tips that people can put into practice, um, if they're worth it, if they're going to actually lead to to big outputs.
Dr Sarah Berry: Yeah, this is another favorite topic of mine. I whizzed over my entire like four years of PhD in about three minutes. I might not be so self-restrained with this area. So I think how we eat is a really interesting new area of research. So we've always thought about, okay, you are who you are and it's all about what you eat. We're starting to understand actually, as I said a minute ago, that who you are also plays a role. But what we now know is how you eat can modulate how you respond to that food. And there's lots of different areas related to how we eat. There's eating rate, how fast you eat your food. There's the time of day that you're eating your food and what kind of foods you're eating at time of day. And we touched on that earlier about the carbohydrate foods, you know, eating it earlier in the day versus later in the day. There's how long do you fast, like in what eating window. So that's where time restricted eating comes in. There's the meal ordering as well. How does what you have for breakfast impact how you respond to lunch? And we've been doing some great research on this. And a new area that I've been involved in and I'm really fascinated by is eating rate. Now, I do think it's important to caveat that the size effect, and I know I've mentioned this before, i.e. how much effect this really has on your overall health will differ from one person to the other. But when we talk about how we eat, I think we can think about it in the way that it brings gives us lots of tools, different tools for our toolbox that we might find just one of these is just easy to integrate into our lives. And actually it's just one extra little tool. It's not going to like transform you, you know, to JLo or. But it's one extra thing to help. And so let's touch on eating rate because this is something we've just published some research on as well. What we know is that the speed in which you eat your food impacts how much food you're eating, is associated with your body weight, is associated with something called visceral adiposity, so it's all that kind of bad fat around your tummy. We also know that people that eat more quickly have higher levels of, um, bad cholesterol, have higher inflammation, have also, um, higher risk of cardiovascular disease and type two diabetes. Now, some of that could be because of the kinds of food they're eating because we know that if you eat an ultra processed food, you eat it 50% more quickly than an unprocessed food. So that's one factor. But there's been fascinating studies, randomized control trials where they randomly allocate some people to eat fast and some people to eat slow. And what they find is that if you allocate people to slow down the pace at which they're eating, then you can reduce their energy intake by up to 65 calories at each meal and over the long term that causes a reduction in that visceral adiposity and a reduction in their overall weight. So it reduces their risk of chronic disease. And that's just a simple method. And so just putting your knife and fork down between each mouthful and slowing down how quickly you're eating the food, you're not changing what you're eating, but you are doing it subconsciously because without realizing it, your fullness signals will be saying, right, I'm full, stop, enough. So you're eating less. Now, not everyone needs to eat less, but in this food landscape that we live in where many of us are eating too much, this is a great strategy if we want to be focusing a little bit on how much food we're eating.
Dr Rupy: And that makes me immediately think of the Mediterranean way of eating, which is, you know, at a table with friends, you know, drinking a glass of wine and stuff and having a chat in between mouthfuls rather than just scoffing down your plate of food, which is something that I do all the time sometimes or if you're in front of a TV and you're not really being mindful about how you're eating or the rate at which you're eating. My question is, how slow is slow? Like how do you even measure eating? Are you literally like telling like, no, you can't.
Dr Sarah Berry: So there's different ways of measuring it. Some ways are thinking how many calories per minute, but I tell you what, that's I don't know if if you want to prepare a meal and work out, work it out that way, that's a bit too difficult. Studies that have shown that if you could extend eating a main meal from around 10 minutes, which a lot of people will eat their meal in 10 minutes, to 20 minutes, that can be enough in order to reduce your energy intake and improve your health. Some of the studies that have shown a reasonable size effect are changing it from about 10 to 30 minutes. So that's kind of a 20 minute increase. Now, again, let's be practical. Is that practical for everyone? I don't know about you, but I cram my food down between zoom calls or during a zoom call. So firstly, I'm probably, I'm not even listening to my hunger signals because I'm so focused on what that zoom call is. Um, but also, you know, it's rushing and this is another problem that although we might, I might say, oh, it's just a simple strategy, put your knife and fork down. I also recognize not everyone can do that. But when I sit at home with my family, my husband wolfs down his food. And I never nag him about what to eat, but I have become a bit of a nag about eating rate. I'm always like, Patrick, please just slow it down. I'm like, you know, we're not in a food race. Now he's brought up in a big family where it was like survival of the fittest. Um, but with my kids now, I am, I've noticed my son, he's like, you know, really. I'm like, Patrick, just slow it down.
Dr Rupy: Yeah, maybe he's modeling his dad.
Dr Sarah Berry: I think so. Yeah. But there's some, I think the simplest way is just put your knife and fork down between each mouthful. For those that like gadgets, obviously there's gadgets you can do. There's this plate called the Mandometer that you can, that you put your plate on and it will buzz if your food's coming off too quickly.
Dr Rupy: Really?
Dr Sarah Berry: There's inflatable knives and forks, or spoon, it's an inflatable spoon actually. Um, that inflates so that it's kind of rigid enough that you can scoop up your food and then it will deflate for a certain number of seconds so that so that you can't then get your food.
Dr Rupy: Oh my gosh.
Dr Sarah Berry: And then it will inflate.
Dr Rupy: Oh, that would infuriate me. It's no way I would use that gadget.
Dr Sarah Berry: Another strategy, use a smaller spoon. And actually there's been some studies that have looked at all of these fancy strategies versus putting your knife and fork down versus using a small spoon. Using a small spoon and putting your knife and fork down, it still has the same effect.
Dr Rupy: Interesting. Oh, that's that's fascinating. I probably wouldn't use the gadgets though, but that is interesting.
Dr Sarah Berry: No, don't waste your money.
Dr Rupy: No, no, no, definitely wouldn't waste that. But it definitely it's made me a bit more mindful about the speed at which I eat my meals because I definitely eat very quickly. But it's because of that, you know, it's usually in between meals, in between meetings and all the rest of it. And in terms of, so we are thinking about food and how we eat food in a very rigid way at this point. So with that caveat, is there any thing that you've looked at with regards to nutrient sequencing? So eating certain types of macronutrients in front of each other to mitigate against, um, uh, snacking later on in the day or glucose spikes and and troughs.
Dr Sarah Berry: Yeah, so we haven't ourselves looked at how specific nutrients themselves impact kind of what happens later in the day. What we do know is if you preload, i.e. before you have a particular food or nutrient, and that's what we mean by the term preload. Um, so if you preload a high carbohydrate meal, so let's say you were to have a bowl of mashed potatoes, let's pretend, or you were to have your delicious seeded crackers, lots of them. Um, if you were to preload that with more fibre, more protein, more fat than is already on them because they're seeded. Um, then that will reduce a little bit the, you know, the blood sugar response. Whether that's going to reduce it more than actually having it as part of the meal, I don't know. And there might be evidence out there. What we do know though from our own research is that what you what you have for breakfast can impact your response to what you have for lunch. So we did a randomized control trial where we recruited 50 people and we asked them in random order to have different types of breakfast. Now, these breakfasts weren't typical breakfast, but they were starchy staples. So by that I mean they were very typical high carb, uh, foods. So mashed potato, uh, white rice, white pasta, white bread. And on different days, every person had these, but across different days, but then they had exactly the same lunch. And what we found was that people's blood sugar, so their blood glucose response to their breakfast, to their lunch meal was partly determined by what they'd had for breakfast. So those people, for example, and I know you wouldn't typically have this, but it's a proof of principle. So it's a kind of the concept of it. Those that had mashed potato for breakfast had a really high glycemic response, so blood sugar response to the lunch meal. Yeah. Yet compared to those that had these other kind of breakfast like the white rice, the white pasta, whatever, even though they had exactly the same lunch meal. So that's illustrative of how what we eat earlier in the day does go on to have impact on how we respond to food.
Dr Rupy: Yeah. Again, it's it's an emerging area and I find that fascinating. There was something recently that I came across, um, where they were experimenting with pre-loading and they found that there was a flatter glucose response over 24 hours, let's say, or in the, uh, hours after that, that, um, intervention. But overall, I think they measured them at six weeks later and they looked at their HBA1C and they didn't really find a difference. Now, whether that's because it's not long enough to see an effect or whether it actually has an overall effect on their propensity towards type two diabetes or, um, improving it or not, I'm not too sure. But there's so much to tease out, I think.
Dr Sarah Berry: Yeah, I think though we have to be quite careful that we don't become what I call single outcome focused. So a lot of these preload studies and you might have heard of the glucose goddess, for example, who, um, has a huge following and does a lot of this kind of preload but N of one, so one person studies where, um, you know, she shows by adding, um, you know, eating your meals in this particular order. So always starting, I think with fibre or protein and then having your carbohydrate, how it can reduce your glycemic response. But your glycemic, your blood sugar response is just one element of how we respond to food. And there's a million other things that are going on when you eat your food. So that I think it's an interesting emerging area, but yeah, I think we have to be careful not to over focus on it.
Dr Rupy: Totally. Yeah. We actually, so we had her on the podcast a few weeks back and we talked about the use of CGMs and how we can't be singular focused on the plate and what you've eaten and the glucose response. So we talked about the second meal effect and how well you've slept, the stress, the, you know, the speed at which you you eat meals and all that kind of stuff is having an effect. So I agree with you. It's it's an interesting area, but it's not the whole. Yeah. Um, it's it's not the whole story. I think where glucose and continuous glucose monitors are good is it's the first opportunity for the majority of people to see in real time what is actually going on inside your body and how food impacts your body in the here and now. Not in 50 years, you know, when you're older and your arteries are all furred and you know, but actually how it impacts you now. And so I think it's fantastic as a motivator often for how to make healthier dietary choices, but knowing that it's only one factor. And it also can illustrate how all these other factors impact us. So for example, from our own research, we show that the faster you eat, the higher your glycemic response. And this is from the continuous glucose monitor. From our own research, we also show that if you've had a poor night's sleep, you have a worse glycemic response the next day compared to if you'd had a good night's sleep, even if you have exactly the same breakfast. So if your kids are keeping you awake one night, you know, and you're having whatever, like let's say a white bagel, you're going to have a higher glycemic response then the next day, let's imagine your kids have slept beautifully. I don't know if you've got children.
Dr Sarah Berry: No, not yet.
Dr Rupy: Well, I've got that to look forward to, I'm sure.
Dr Sarah Berry: But, you know, let's say that they've had a good night's sleep or whatever, you've not been out late or, you know, that that all impacts it. We see, you know, there there's like the shift work, you know, all of this. When you're wearing a continuous glucose monitor, you can see how actually it's so much more than just what I'm eating. My stress, I'm stressed today, the cortisol levels, that impacts it. Oh, the time of day that I'm eating. So I think that the use of continuous glucose monitors in healthy individuals is incredibly contentious area. Um, if you go on Twitter or X as we call it, oh my gosh, it's like wars out there.
Dr Rupy: I was going to say, yeah, because a lot of people would say CGMs could come should come with a health warning. And this is actually coming from, you know, other dietitians, nutritionists, like people are really, really anti the use of these CGMs. Now, I'm, I think it depends. I think it depends on the individual, whether this is going to lead to unhealthy obsessions with healthy eating. I think on balance, I agree with you. I think it's a really good motivator. I think from a behavioral change perspective, patients that I've had in the past have found it, uh, a light bulb moment when it comes to figuring out what is spiking them and actually how they can take more control of their diet. But there's a lot of people that disagree.
Dr Sarah Berry: Yeah, so I think there's various arguments. There's the arguments that by using continuous glucose monitors in healthy individuals, you're taking it away from people living with diabetes, type one, type two who need it. That's a moot argument because there's no issue with supply. There might be an issue with whether there's funding on the NHS for every patient to get them, but that's nothing to do with healthy individuals. There's the argument about whether they're accurate enough and repeatable enough. And so there's been various papers published in this area. I don't know if you've seen them. Um, so there's a scientist called Kevin Hall that published a paper saying that actually they're not accurate enough, they're not precise enough. And if you're using them in the area of personalized nutrition, which we often call also precision nutrition, because you have to be so precise, if you're basing your advice around a monitor that's giving you imprecise results, then that's wrong. We've since tackled that. We've done our own research where we had 350 people wearing uh, the same monitor on each arm. So at the same time, we find that actually we believe based on our evidence, they're very precise. Um, then there's the argument around health anxiety. You're going to get that with any of these wearables. So, you know, I wear health trackers. Um, I'm not particularly interested in, I don't look at the things that much, but I know some people that are obsessed with, oh, my heart rate variability went up because I had an ounce of alcohol or, oh my gosh, you know. It's like, okay, but how did you feel? How do you feel now? Fine. So then don't worry about it. Um, when people are seeing in real time, holy shit, these metabolites, my glucose is changing. Look what about this peak. Yes, that is a problem. We don't want to cause health anxiety. And it's about making sure people are properly informed about what is too high, what's not too high, and just told, look, it's a normal physiological response. If you flatlined, you know, are you just eating red meat all day? You know, it's normal. Don't worry about it. So it's about educating people on really being able to look at it and also interpret how they're feeling. And the example I used earlier about how I didn't realize I was getting these dips after breakfast. And it wasn't till I, and this is despite 20 something years of nutrition research. It wasn't till I wore the monitor I was like, oh my gosh, it made sense. So now I have actually changed the kind of breakfast I have, which used to be really refined carbohydrates because I'm one of these people that needed the evidence to. So it's giving me that evidence. So it can be used in a sensible way. And then the last big problem with it is people become glucocentric. And I think this is the big problem. And I could go and eat a diet that caused me to have the most wonderful readings on the continuous glucose monitor, but it could be the most horrific diet. I could just eat butter and red meat all day. That's not a healthy diet. So it's about how you use the tool is what matters. And I actually think that if people are properly educated and if it's used in combination with, which is what we do with our Zoe predict studies, with lots of other different outputs that we measure, then I think it can be a useful tool.
Dr Rupy: Yeah, yeah.
Dr Sarah Berry: I think the point around being too glucocentric is really important. And actually, I had that conversation with Jesse, who is the glucose goddess and everything. And you'd think that she is too glucocentric. She completely gets the, um, the gamification of this. And if you were to just focus on flatlining, you would just be having oils, red meat in your diet, and you would get a wonderful reading. So you have to really think wider about the the impact of these products. And I, you know, I think as somebody who is in the public eye, putting out healthy recipes, even that can be construed as unhealthy for certain people as well. It can make them too obsessed about making sure they've got nuts and making sure they've got greens and fermented foods and all that kind of stuff. And, you know, I personally wear a wearable and I check my,
Dr Rupy: Oh, you got the ring on as well.
Dr Sarah Berry: Yeah. I'm not sponsored by them or anything. But I found it very useful for me as a tool. I know my wife would absolutely hate it. She's like, I don't care about my HRV. And even me, I know if I have two glasses of wine in the evening, it completely messes up my score. And it annoys me, but I find that a bit of a deterrent first off, but I'm also pragmatic enough to just ignore it and enjoy the glass of wine when I do want to, um, as part of my, you know, healthy balanced week. So I think it really depends on the individual is my point.
Dr Sarah Berry: I think it does. I think what we need to be really careful about with wearables, with tracking, is that we don't forget how to listen to our own signals. Our bodies are so clever. You know, our bodies are designed to tell us when we're full, when we're hungry. Now, okay, if you start yo-yo dieting, unfortunately, you you muck that up and yes, we're in this awful like, you know, food landscape that we're not evolved to handle. But our bodies are clever. And this is what worries me with the wearables is I hear people say, oh my gosh, I had whatever last night and this has happened to my heart rate variability. It's like, okay, but how did you feel? How do you feel now? Fine. So then don't worry about it. Um, and I think that's what we need to be really careful about. And this is, you know, with my, I never tell my children you can't have more. Well, I do with Haribos, but actually if they want, if we're having a meal and they want seconds or thirds, fine, because I want them to learn to listen to their hunger signals. And I see too many parents around where they're, I'm like, that, but that's a lovely healthy meal. If they're hungry, allow them to feel when they're full. And so very little is off limits as well with my kids because I want them to also know, do you know what, I don't feel great when I've eaten a whole bar of chocolate. So my daughter likes chocolate, but she actually knows because she's had free access to it, that she's 14 now, she knows actually if I eat that whole huge bar, because I've allowed her to in the past, I actually feel a bit crap afterwards. If we don't allow children and ourselves to work out our own signals, to rely on technology too much, I think is a is a danger.
Dr Rupy: Yeah, totally.
Dr Sarah Berry: But again, different things, different people.
Dr Rupy: Totally. Yeah. And chocolate wise, which what's your favorite chocolate? I had to ask you.
Dr Sarah Berry: So my favorite chocolate, I I'm toying between Galaxy and Dairy Milk. Now, what's the healthiest chocolate? Is a is a very dark chocolate. So not Galaxy or Dairy Milk. But I like the taste of Galaxy and Dairy Milk. I'm not eating it all day every day. So
Dr Rupy: Yeah, yeah.
Dr Sarah Berry: I've acclimatized to the taste of really dark chocolate. Like I'm I'm such a dark chocolate snob. I'm very snobby with my coffee. Do you drink coffee?
Dr Rupy: No, I'm a tea, I'm a tea drinker.
Dr Sarah Berry: Really?
Dr Rupy: Red wine drinker, white wine drinker.
Dr Sarah Berry: So you just don't like the taste of coffee or?
Dr Rupy: No, I love the smell of it.
Dr Sarah Berry: Ah, okay.
Dr Rupy: But not the taste.
Dr Sarah Berry: No, I don't like it. My husband's into all his different coffees.
Dr Rupy: Oh, really?
Dr Sarah Berry: But no.
Dr Rupy: Okay. Oh, that's interesting to know.
Dr Sarah Berry: I love a Yorkshire tea with a bit of semi-skimmed milk. I'm a simple kind of girl. I'm sure you're you're seeing that.
Dr Rupy: I love that. I love that. That's great.
Dr Sarah Berry: I get my husband brings me at quarter past seven every morning as he's walking out the door, a mug of Yorkshire tea, tiny bit of milk. I go through all my emails and slacks and then I'm ready for the day.
Dr Rupy: Sounds idyllic. Not not when you see how many emails and slacks are coming overnight. Um, I wanted to ask you about the Zoe method study. Have we already talked about that?
Dr Sarah Berry: No.
Dr Rupy: Okay, fine. So this is different to the predict.
Dr Sarah Berry: Yes. So, um, perhaps I can pause and tell you a little bit about the research at Zoe. So Zoe was set up about seven years ago, um, as a kind of quite unique collaboration between a startup tech company, which was Zoe, um, and a collaboration with traditional academics. So myself, Tim Spector and some other universities. But on the academic side is led by by Tim and myself at King's College, London. And what we wanted to do is we wanted to see if we could improve the health of people by seeing if we could understand why people respond so differently to foods. So how how differently do people respond to food? How differently do people respond day-to-day? We talked a bit about that. What is it that's causing this variability in responses to food? You know, is it our age? Is it our sex? Is it our microbiome? Is it our genetics? And actually, can we collect enough data in order to predict based on certain metrics how you respond to a food versus how I respond to a food. And the reason we wanted to do this is because we know that diet related diseases are growing at an alarming rate. We know that there's some great population-based guidelines out there. So guidelines for everyone in the population to follow that are underpinned by actually very robust evidence in most instances, not in all instances. But the problem is people don't follow these guidelines. Less than 1% of people actually follow the UK dietary guidelines. So firstly, they're not working because people aren't following them despite this good evidence. Secondly, we know that everyone's responses are so different. And so, you know, when I talked to you about the almonds, so the fact that some people are absorbing 170 calories, some people only 60 calories. Do we want to give the same advice to everyone? So can we conduct really large scale research in order to understand how different people respond to different foods? So we've conducted a series of studies which are called our predict studies. And so I've referred to our Zoe predict findings. And these are really unique studies because this these are studies that are collecting data at a scale that's never been done before. So we've now got data on 150,000 people. My, I've run 30 randomized control trials before I started working at Zoe. The biggest one of these had 50 people. Now, size isn't everything. But and there are some cases like with my traditional studies that I've done at Kings where you need these really tightly controlled studies. But to start to unravel how different people behave differently, we have to get this kind of scale. So we've been collecting data at a scale of breadth, so loads of different measures, which is why I've been able to talk to you about sleep or menopause or eating rate or, um, a precision, so making sure we use a really precise tool. So hence the precision of using tools like continuous glucose monitors is so important to us. Um, and a depth that just hasn't been done before. So we've got this huge, we've got this gold mine of data. And what that's enabling us to do is to understand how much variability there is, but what's causing this variability and therefore build kind of predictions in order to give you advice on what's best for you to eat versus what's best for me to eat. Now, there's some underlying principles, and I know I mentioned this earlier, that are healthy for everyone. So everyone should eat more fibre. Everyone should increase the diversity of their plant-based foods. Everyone should reduce ultra processed foods. But there's lots of subtleties in how you could eat foods that are better for you than they are for me. And so that's been the idea behind all of our predict studies. But then we wanted to put it to the test because it's all very well doing all of this research, but we are a science-based company. I'm a scientist at Kings. I don't want to be advocating anything unless we have any evidence. And so we recently completed a study called the Zoe method study. And the aim of this study was to look at how do people's health, how does people's health change if they follow population-based guidelines versus following the Zoe program. And so what we intentionally did is we, so we recruited people and we asked them either half of these people, 150 people, can you follow, this took place in the US, the US my plate guidelines, which is similar to the UK eat well guidelines. We did what we call standard care, which is often an approach we use in nutritional research where we delivered the advice in the standard way it would be delivered, like with leaflets and a little video. And then we left them to their own devices, but they had access to some of our nutritionists if they wanted advice. Then the active arm as we call it in nutritional research was the group of individuals, another 150 people who were allocated randomly to follow the Zoe program. So these people were provided with a test kit. Now this is similar to a commercial product that that Zoe have. Um, so we tested all sorts of things that we know impact how you respond to food. They had a continuous glucose monitor. We collected dry blood spots, so finger prick samples to look at hundreds of different metabolites. We, um, uh, collected a poo sample for for the microbiome. We collected lots of information about what they were eating, when they were eating it, how they were feeling. And then after that, they're provided their own, uh, special scores related to food and they then enter this Zoe program phase where for 12 weeks they follow the Zoe program which includes access to nutritionists, it includes day-to-day lessons about how food impacts your health and it includes the access to their own scores for each food. And then at the end of the 12 weeks, uh, we looked at how different health measures had changed, how their weight had changed, how their apoB, so a really important measure of cholesterol changed, other measures of cholesterol of insulin sensitivity, etc. And what we found is for those following the, uh, Zoe program, they had significant improvements in weight, um, really significant changes in waist circumference, which we know is actually more important in terms of a risk factor related to to disease. They had significant improvements in triglycerides, which is a circulating level of bloods, um, and improvements in other health measures compared to people following the population-based advice. But a big potential criticism of the study is, well, hold on, you didn't match the kind of approach that was given. So you didn't match the fact that people following the Zoe program have this amazing app that's all singing and dancing. Now, both had access to similar access to nutritionists, but we didn't match for the app. And we intentionally didn't because we wanted to look in again in that pragmatic way. We wanted to take it away from the really kind of very sort of traditional RCTs and say, well, look, this is what's happening in reality. So what we were able to do with our analysis, and this is what's great about when you dig into the data, you can often adjust for some of the limitations of the study. So we looked at a group of people who were really, really adherent. So followed really closely to the, uh, population-based guidelines. And then we looked at the group of individuals that were most adherent as well to the Zoe program guidelines. So we're removing away the confounder of, oh, well, they just followed the diet more. And when we looked at adherence, we saw even greater difference actually. So we saw that those that were more adherent to the Zoe program actually had even greater improvements in apoB, for example, you know, this very important metric related to heart disease, in waist circumference, in, uh, weight as well. And I think that illustrates the promise for personalized nutrition. But also the importance of thinking about the many different features. Because we include lots of the different features in that. It's not just about glucose.
Dr Rupy: Yeah, yeah. How many people were in the study?
Dr Sarah Berry: So we had, the study was powered to have 150 complete each arm.
Dr Rupy: Each arm. Okay, so about 300 total. Something like that. Okay. That's super interesting because that would have been my first thing as well. Like if you have this wonderful program that I've done a couple of times and you're accessing a health coach and it's all very targeted and there's almost this ceremony around starting this program by having your blood tests and all the rest of it, that would improve motivation and adherence. But if you're controlling for adherence, that's really interesting. And I guess like if you were to repeat the study, what would be interesting is if you actually prepared the meals, which is hugely expensive, of course, for 100 odd people, um, and actually gave them standard of care diets through plates and then the the Zoe plate, let's say, just to see if there was actually that difference because the first thing that came to mind when you mentioned how less than 1% of the population follow dietary guidelines is surely the first step in trying to improve everyone's health across the UK is just to get people to help people follow the dietary guidelines, right?
Dr Sarah Berry: Yeah, absolutely. But people aren't following them. So how can we help people follow them? And there's really interesting research that shows that if you tell someone the advice we're giving is personalized to you, all of this, these different biological features, your genetics or anything, that actually they go on to improve their diet a lot more than people that are just told the dietary advice is generic. You know, it's general. Even if it's exactly the same. And that's the power of the belief in it's something personalized to me. And I think something that we have to be careful not to kind of knock is that there's some advice that we might give, I don't mean Zoe, I mean generally as nutritionists or or, you know, uh, clinicians, that might have what we call a small size impact. So actually might not make much difference. But if that's a motivator for people, and if that can then motivate them to make what will actually make a huge difference. If everyone just started eating a load of pulses, I mean, we'd improve the health of the nation overnight. But people aren't going to. But if we tell them something sexy about those pulses, how it impacts some, I don't know, something that they think is like, wow, that's so scientific and novel. Yeah. Yeah. If that gets them doing it.
Dr Rupy: It's it's funny. I was chatting to a a colleague of mine the other day about, um, the use of psychedelics. And this is completely like off topic here. But the use of psychedelics and she was like, wouldn't it be interesting if we added the same sort of gravity and use of ceremony that people use when they have a psychedelic experience and applying that to like sertraline or SSRIs or something that we tend to give in a very sort of like matter of fact manner in a GP office. You know, what I wonder what the effect size would be. I wonder if that would actually have a difference in someone's appreciation for the for the drug and all that kind of stuff. So it's it's there's a similar parallel there. Obviously, we're not talking about psychedelics here, but there's a similar parallel by giving people a better understanding of exactly how much they are going to be impacting their body and how precise this is and how scientific it is.
Dr Sarah Berry: Yeah, I think that people don't fully realize how much diet can impact their health. I think that you've got a small group of the population that do. And they're the people that we probably don't need to target that much that, you know, we would just be shaving around the edges, optimizing. But where the real problem is is is very difficult to tackle.
Dr Rupy: Do you think precision nutrition is the way to tackle that, the the major population?
Dr Sarah Berry: I think there's a large part of the population that no one's going to tackle. And this is because we know that our food landscape is awful, that there are a huge amount of people that don't have the luxury of the head space to think about what they're eating, what food, how to prepare healthy food, or, you know, they're surviving day-to-day with making sure that they can pay for the heating bills or, you know, etc, that it's just not a priority. So how we can make it a priority for people, I don't know, that's for behavioral scientists, government to to to sort out. I think that there's an area that's often overlooked when we talk about personalized or precision nutrition, which is stratified nutrition. And by this, I mean where we group people based on shared characteristics. And so we don't have to jump from population-based straight to that personalized. There's a huge area in the middle. And the learnings that we can use from all the work that we're doing, for example, in the area of personalized nutrition can guide us in the stratified way. So a great example is giving advice based on whether you're pre or postmenopausal. So that means you don't have to go and do all these fancy tests, you know, just knowing whether you're pre or postmenopausal, we could give dietary advice that's slightly modulated to maximize health. Um, based on age, based on, you know, sex, like there's lots of ways we can improve people's health in a stratified way that's therefore more accessible at a population level without needing many tests. Now, you can even in a stratified way go really deep dive if you wanted to. So we talked about how time of day matters. So we know if you have carbohydrates in the morning versus the afternoon. Well, what we know is for younger individuals, the time of day effect seems to be really pronounced. So for younger individuals, if you have carbohydrates in the morning, you have a really much lower glycemic response, so blood glucose response compared to if you have it in the afternoon, it's a lot higher. As you get older, the time of day effect is less pronounced. So using that kind of stratified approach, if you were going into the depths, but, you know, wanting to give advice about the time of day that you have your carbohydrates, we don't need to be advising these 60 plus year olds that actually the time of day is really important based on our research because it doesn't seem to be as important. But for younger people, we might want to. We don't need to do any tests for that. That's just based on age. So there's lots of advice I think where we can reach that middle ground. But I think the big problem is is that we're eating too much ultra processed food. We're not eating enough fibre. We're not eating enough unprocessed food. Precision nutrition is not going to solve that big problem. How we solve that is a huge problem.
Dr Rupy: Yeah, yeah. We can pontificate about that the rest of the podcast actually. I think the idea around the processed foods and actually improving the nutritional quality of those is something definitely to, um, to think on. You mentioned pre and post menopause now. So using that sort of stratified nutrition approach, how would you advise different groups of people, uh, in those individual categories according to the the general principles of of what they should be thinking about when it comes to nutrition?
Dr Sarah Berry: Yeah, so I think the first thing to say is that there's no silver bullet when it comes to diet and menopause and, you know, you look on on the internet and there's these supplements out there that will cure you of your brain fog, your anxiety, your hot sweats and everything and will make you look like JLo overnight. I mean, what they're promising is phenomenal. Now, if it has a placebo effect, great. If you can afford it. If you can afford it and it has a placebo effect and you feel good, fine. You know, I don't think these are doing any harm. But actually the evidence to show that diet reduces menopause symptoms or particular, you know, there is a silver bullet, you know, is not strong enough. What we do know though, however, is that overall healthier dietary pattern, and that's a very boring message, I know, can actually significantly reduce your menopause symptoms. We know that from again, our Zoe predict research, we know that from other published research. If you shift from an unhealthy, highly processed diet to a more Mediterranean style sort of diet, general healthy dietary pattern, you do reduce the severity of your symptoms by up to 30%. Are there single foods that will cure your symptoms? No. We do know that phytoestrogens found in soya, um, for some individuals have quite potent effects and might help reduce your symptoms, but you have to be having a reasonable, um, amount. But in terms of kind of advice of how, yes, just based on someone's being pre or post, what we know from our own research is that postmenopausal have a lot larger blood glucose response to a carbohydrate meal than premenopausal. And so if there was someone that was at risk of type two diabetes, for example, and we wanted to give them advice on the kind of foods to to eat, we might give a more targeted approach to the postmenopausal woman because we know on average, they're having a worse blood glucose response to a meal than a premenopausal woman. So that's where you can use that kind of stratified approach. I went around the houses to answer that, but that's because there's a new paper that just came out yesterday stating that diet could cure menopause symptoms. Um, which it can't. And so it's going to be in the news a lot over the next few days. I don't know when this podcast is coming out, but I think it's really important to say to people, just be a bit careful with the promises that are out there to do with menopause.
Dr Rupy: I haven't come across, I haven't come across that yet. I'm sure I will.
Dr Sarah Berry: I think it came, it's out, it would be either yesterday or today.
Dr Rupy: Where was it published? Oh, it doesn't matter. Don't worry, I'll find it.
Dr Sarah Berry: It's been covered by lots of newspapers yesterday or this morning.
Dr Rupy: Oh, I'll look that up for sure. Yeah. And in terms of protein as well, because menopausal, postmenopausal women usually inquire about protein as, you know, the risk of sarcopenia increases, so the the loss of skeletal muscle and, um, the, uh, the impact on osteopenia. What are your thoughts on protein? Do the protein requirements increase as we get older generally and particularly in that postmenopausal?
Dr Sarah Berry: So, do you know what, whenever I do a podcast, I think the worst question I can get asked is about protein.
Dr Rupy: Really? Oh, sorry. I was doing so well.
Dr Sarah Berry: Or or about genetics. But because I only like to talk about what I feel I have really great expertise. Protein's such a tricky one. It really is because you have researchers that are working on protein related to, you know, physical activity, endurance exercise, like eat loads of protein, you know. And then you have the evidence related to aging. I don't think we have clear enough consensus around protein. There is a huge move, particularly in the US, that, you know, it's all about protein. That it's becoming now the new thing, I think. You know, we had fat that was demonized, we had sugar that was demonized. Then we have, you know, all our super things. And I think protein's this next hot topic because I'm being asked about it. I think for the majority of the people in the UK, we're getting enough protein. There's very small segments of the population that aren't getting enough protein. I think that for postmenopausal women, for older individuals, yes, our requirements are slightly higher because we don't metabolize it quite as effectively, uh, for example. But I think for the majority of people, if they're eating a broadly healthy diet, and I know it's a boring message, if they're eating a broadly healthy diet, I don't think kind of supplementation with like protein powders, etc, is necessary. But it is a time to be making sure that you are getting protein in your diet.
Dr Rupy: If you were to put, and with the caveat that this isn't your area of expertise, if you were to put numbers on the amount of protein that people should be thinking about consuming per day, what are we, are we looking at 1.5 to 2 grams per kilogram or is it less than that? Or do you not want to say?
Dr Sarah Berry: Uh, I would say for healthy individuals, it's definitely less than that. I don't think there's any evidence to show that above 1.2 grams per kilogram unless you're kind of bodybuilding, um, has any beneficial effect. I think for older individuals, yes, the numbers might be higher, like 1.6, but I'd like to caveat that by saying it's not my area of expertise. Um, and my general feeling on protein is that for the majority of us, we shouldn't be worrying about it.
Dr Rupy: I I I'll give you, um, the context as to why I asked you about that. Um, because I agree with you, it's now become quite trendy to talk about protein. It's almost like it's having a resurgence because when I was getting into nutrition, like, you know, 10 years ago and just more than 10 years ago now, and learning a bit about it, it was all about protein. And that's why you see all these packets with like high protein this, etc, etc.
Dr Sarah Berry: Because of keeping you, that was around the time, I think probably about protein being satiating. So keeping you full for longer.
Dr Rupy: Yeah, full for longer and great for muscles and all the rest of it. Um, but now, uh, and I agree with you, I think over a population, as we generally eat meat and fish and everything, um, we're getting enough protein from our diet. As people transition to more plant-centric diets, not even vegan or vegetarian, but plant-centric, and they're gradually taking that meat out of their diet, over 24-hour periods, they're probably getting less protein. And so when we talk about diversity and getting legumes, what are we replacing? We're replacing the meat and the fish and all the rest of it. So at that level, it is a bit of a concern at the back of my mind as to where people are getting good sources of protein from that's bioavailable and, you know, meets the the standard requirements.
Dr Sarah Berry: Yeah, I think you're right that whilst I think the majority of people are getting enough protein, I think that for people that are transitioning to a more vegetarian, vegan based diet, then they need to be mindful of getting enough protein. But the important message I think is that you can get enough protein on plant-based diets. But it's interesting, I was in Vancouver, uh, last week presenting at a conference, um, and all of the lunch places that I went to would have all these kind of healthy plant-based dishes to choose from. Then they would all have a protein section. And it was labeled protein. And so I would say, oh, can I have this, this and this? Yes, what protein do you want with that?
Dr Rupy: Yeah.
Dr Sarah Berry: They wouldn't say, do you want fish, tofu, you know, um, uh, or a meat. They would actually say what protein you want. They were talking about these foods in terms of protein and not the food. I found that really strange.
Dr Rupy: You know, they do that a lot in America. I remember going to salad bars and all this kind of stuff and they're like, what protein would you like with that? I was like, oh, it's got chickpeas, it's got edamame. I'm like, I don't need anything else. I'm just. But they it's it's weird that's almost in our vernacular, isn't it? To to think about it. Well, it's certainly in America.
Dr Sarah Berry: And it will probably, it will probably see it here soon.
Dr Rupy: Oh, yeah, yeah, 100%. We'll definitely see that.
Dr Sarah Berry: Well, the fact that I keep getting asked about it. I'm going to have to start reading up on it rather than telling people I don't know.
Dr Rupy: There's a few areas actually that I'll I'll send them over to you afterwards. I want to ask you two more things. So I I we've been talking for quite a while now and I want to get you in the kitchen. And um,
Dr Sarah Berry: You haven't seen me in the kitchen before.
Dr Rupy: Um, there is debate over the oscillations of glucose as measured by CGMs and whether that actually corresponds to a worse outcome metabolically. So type two diabetes and all that kind of stuff. What do you say to people, particularly online and maybe even on Twitter, even though I try not to go into it at all personally. What do you say, how do you respond to that? What's the evidence to the contrary?
Dr Sarah Berry: So I think a lot of the evidence is with people with type two diabetes or type one diabetes. So people living with diabetes, much of our evidence comes from. Outside of that within healthy individuals, which is where a lot of the contention is. There is evidence from our own research and we actually have a paper that's under review specifically related to this. And then also there was another study published recently. There's lots of different features of the glucose response that you can look at. So one is these oscillations. Another is how much time are you spending in range, you know, within a healthy limit. Another is the dips that we talked about. I think that different features matter for different outcomes. And I think again, I know it's nuanced, I know it's a bit complicated. So our research shows that the dips, like I've said, is really important in terms of your energy levels and your calorie consumption. We know from our own research that the peaks that you get, so after you've had a high carbohydrate meal, how high you go is very strongly related to an inflammatory response. So you might spend quite a lot of time at a certain level, but it's that kind of peaks and troughs is quite closely related to inflammation. There isn't enough research to say what matters more yet in my opinion, because this is I think what's discussed a lot and what even we get asked a lot at Zoe. Oh, I'm in a tight range, um, you know, but it's at the high end of the range or, oh, well, um, on average it's quite low, but I'm getting lots of peaks and troughs. What matters more? I don't think there's enough evidence to say yet. I think that there is enough evidence to say that excessive peaks and excessive troughs over an extended period of time is associated with an increased risk of cardiovascular disease. And our paper that's under review at the moment shows that in healthy individuals, these excessive peaks and troughs, so what we call glucose variability, is closely associated and more closely associated with cardiovascular risk measures than just taking a kind of average point in time glucose. But a lot of the data at the moment from using continuous glucose monitors in healthy individuals is what we call association data. So it's data that's taken at one point in time. In 20 years as we follow these people up, we'll be able to say with more, you know, rigor what actually, you know, the strength of the evidence is.
Dr Rupy: Yeah. I think that's a really good point about the different, the different characteristics of glucose monitoring because I don't think people appreciate there's oscillation, there's troughs, there's, you know, time in range. And that's a really good point. And the fact that we don't know too much at this point, I think it's really important to be honest about that as well.
Dr Sarah Berry: Yeah, absolutely. You know, science is evolving at a, you know, crazy rate. It's such an exciting time to be in nutrition research. And I always tell my students this that they are so lucky, we are so lucky because we now have novel technologies, whether it's continuous glucose monitors, whether it's your ring telling you your heart rate variability, etc. Whether it's that we can conduct remote trials where people can take a, you know, saliva sample for DNA, a poo sample for for the microbiome. I think at the moment, research is on steroids. You know, it's evolving, it's like on fast forward. It's crazy how fast our understanding is evolving. And I think that it's for for me as a researcher, it's exciting, but I think for lots of people, it's frustrating because it's like, whoa, hold on, we were told this, you know, five years ago, now you're saying this or, oh, you know, continuous glucose monitors, you're saying this, but we're not quite sure about that. Science isn't an exact science. And, you know, we can give our best interpretation of the evidence. We can do what we think is most rigorous and robust. But things will evolve and our understanding will evolve. And I think that's why for me as a researcher, it's exciting, but I think for individuals trying to pick the best diet, I probably accept that it's a bit frustrating. In which case, just have more fibre, more pulses, more diversity, go back to the basics.
Dr Rupy: Yeah. Sarah, you're awesome. I I love your realism. I love the fact that you're pragmatic. I like the fact that even, you know, after doing this research, you're not 100% perfect. I think that's really reassuring for a lot of people. So I appreciate you being super honest on this pod. It's been a pleasure. Absolute pleasure.
Dr Sarah Berry: Thank you. It's been fun.
Dr Rupy: We're going to get you to the kitchen now. It's a different story.
