Dr Rupy: These are my evidence-based recommendations for specific foods you should be eating every day to lower cholesterol. We've done a full dive into what cholesterol is, why we need it, how we measure it, and why it's important to get certain measures of cholesterol in our blood down to as low levels as possible on episode 202 of the podcast. So if you want more information about cholesterol as a molecule, I would 100% recommend that you go and listen to that podcast first. Today's episode instead is specifically tackling the foods and doses of foods that I personally consume daily to keep my cholesterol levels in check. And as part of a heart-healthy protocol, I feel these additional ingredients can be safely added to most people's diets with positive results. Remember, you can watch the podcast on YouTube, just click the link in the caption. And if you want to support the podcast, the easiest way to do that is to subscribe and hit the notification bell on Apple and Spotify. And if you're going to watch this on YouTube, make sure you subscribe and hit the notification bell there as well. It's a small thing, but it really does help us out and it helps the podcast get to as many people as possible, which is exactly the mission of the Doctor's Kitchen. You can also subscribe to our newsletters for free. The links to all which are down below where we serve recipes and we give you lots of information to not just give you empowering, healthy information about food and lifestyle, but also put a smile on your face as well. For now, onto my podcast about how to lower cholesterol with food.
Dr Rupy: These are my evidence-based recommendations for specific foods that you should be eating every day to lower cholesterol. So not only do these foods specifically reduce cholesterol, but consumption of these foods have been shown to improve overall cardiovascular health and may have additional benefits for things like brain health, gut health, mood as well. So this isn't just about cardiovascular health, this is about a plethora of other things. We need to establish a few things before we get started by talking about these foods. So heart disease can be caused by many factors, including genetics, and not all of them are things that we can control. But atherosclerosis, also referred to as inflammation or scarring of arterial vessels, can be influenced by things like lifestyle. So physical activity, sleep, psychological stress, and yes, of course, diet. And research finds that adding certain foods to your diet could help lower cholesterol that contributes to atherosclerosis. Cholesterol is a very controversial subject. I've done an entire podcast on cholesterol, what it is, how we measure it, why lower is better. I'm not going to go into that right now. My editor is going to put a link to that somewhere on the screen or in the captions, but you'll just have to assume that this is what we need to do to improve heart health at this point. Lower is better. We've based a lot of our recommendations today on this fascinating 2021 systematic review that was published in nutrition, metabolism and cardiovascular disease in 2021. If you look at the screen, you'll see if you're watching this on YouTube, I'll explain what you're seeing. There's a selection of different categories and specific foods that have a cholesterol raising and a cholesterol lowering effect. So that's on the Y axis and then across the X axis, you've got all these different foods, and you'll see a lot of the plant-based foods have a protective effect and a lot of the animal-based products and sugar has a negative effect. We've also combined that information from that systematic review with some of our own research as well. So, let's get started. Here are three foods that may keep your cholesterol levels in check and support heart health. Number one, nuts and seeds. So this is a big category. It includes everything from flax seeds, almonds, hazelnuts, walnuts, there are nine tree nuts. I'm a big fan of all of them, and lots of different types of seeds. So flax seed is yes, a type of seed, but there's also sesame, pumpkin seeds, sunflower seeds, these are all fantastic. And we're going to dive into the benefits. High consumption of nuts has been linked to reduced risk of cardiovascular diseases in several prospective cohort studies. One systematic review on tree nuts conducted in 2015 with 42 randomised control trials and over 2,000 participants found the small but highly significant reduction in LDL cholesterol, which is a measure of cholesterol that I'll be referring to a number of times today. So what is in nuts that gives these potential benefits? Well, they provide many nutrients that can help lower lipid levels or keep them in check. Vitamins, including vitamin E, vitamin B6, niacin, which is also vitamin B3, folic acid, which is also vitamin B9. I should just call vitamins by their B nomenclature, but they're known both in academic spheres and online as niacin and folic acid, so I'll refer to them interchangeably. They also contain minerals as well. So magnesium, potassium, copper, dietary fibre, plant protein, specifically arginine as well. And they also have phytosterols and phenolic antioxidants as well, which may explain some of the benefits. So how do they work? There are three potential mechanisms. Number one is the satisfying crunch factor. So the actual mechanical action of chewing nuts triggers the release of hormones that tell our brain that we are full. Essentially, it is an appetite suppressant or a natural Ozempic if that's how you want to refer to it as. And if you stimulate these appetite suppressant hormones, it can obviously promote satiety and lower your energy consumption in your 24 hours, lowers your overall fat intake, and the bioavailability of that fat content in nuts is actually quite low if you're eating it in a whole form. I should establish that when you're eating nuts and when I'm telling you to eat nuts, the sort of spectrum of what constitutes a better nut than another one is you've got whole nuts. So if you're just eating it straight from a jar or peeling a pistachio and then eating that, that's one way. Then you've got the butter of which you've got crunchy and smooth. So crunchier is closer to the whole nut than smooth, which is a bit more processed. And then you have flours. So flours are when they are completely pulverised and some of the fat is actually extracted, so you're losing some of the nutrient value as well. So in terms of when we're talking about nuts, you really want to be eating more whole nuts rather than the processed forms of nuts, particularly the ones that are added or covered in chocolate and sugar and all that kind of stuff. Those taste great, don't get me wrong, but you want to be having more of the whole unadulterated nuts themselves. So one way is in which it can lower cholesterol is that it actually encourages you to reduce your energy intake over 24 hours. And a lot of the fat that is actually not absorbed is excreted in the faeces as well. Number two are these phytosterols. So phytosterols are particular types of nutrients that can actually impair the absorption of cholesterol because their hydrocarbon molecule is larger and has a greater affinity for something called micelles than cholesterol. So micelles are related to how cholesterol is transported and absorbed by the body. And as a result, cholesterol is displaced from that transporter molecule and the amount available for absorption of cholesterol becomes limited. They're kind of like cholesterol's worst nightmare. It's kind of like if you've ever had an experience going on an underground train in the middle of London and it's a packed train, these nuts phytosterols, they kind of just grab the cholesterol, chuck it off the train and they jump on the train themselves. That's basically what's happening with these phytosterols and that's why it can have this cholesterol lowering effect. So phytosterols, if you can consume them in the form of nuts, not only are you getting all those nutrients, but that is potentially one, just one way in which they're also having a cholesterol lowering effect. Nuts are also a great source of protein, particularly L-arginine, which is usually recommended for people with dyslipidaemia. And it's been suggested that this amino acid L-arginine can improve lipid profiles by increasing nitric oxide production. We've talked about nitric oxide a lot on another podcast where we talked about how it is produced, why it has a vasodilating effect. So vessel dilating, making larger effect, which can lower blood pressure and improve overall cardiovascular health. This also increases the activity of lipoprotein lipase, an enzyme that degrades circulating triglycerides in circulation. So this increase in nitric oxide production can increase the activity of lipoprotein lipase. This is an enzyme that degrades circulating triglycerides in the bloodstream, which improves the hydrolysis of triglycerides and then overall helps lower the levels in our bloodstream as well. So triglycerides are a particular type of fat. They are produced by the liver. Reduction of which is associated with improved cardiovascular outcomes. So there's a number of different ways in which nuts can improve cholesterol. The other thing about protein is that it is particularly satiating. So again, as well as the satisfying crunch, the increase in appetite suppressant hormones, the protein being satiating can also lower your overall energy intake in a 24-hour period that has also been shown to improve cardiovascular diseases as well. So, how much should you have of these wonderful ingredients that have this potential benefit? 30 grams a day or a small cupped handful of nuts every day is something that I would start off with. Mix it up. You can get a whole number of different types of benefits from the plethora of nuts that we have. Some people like walnuts, some people find them a bit bitter. Pistachio, I find them quite sweet. I think they're beautiful just on their own. Use as a topper. Just try adding nuts every single day, just a small handful. And if you wanted to do a little experiment, try and check your cholesterol levels at day zero, try all these different things that I'm suggesting, and then see what your cholesterol levels do after 30 or 60 days. I would try 60 days if you can manage that long, but it'll be really interesting to see what happens. You can also get phytosterols in other foods. From nuts, they are the highest, but you also get them in vegetables and whole grains as well. In fact, there was a controlled feeding study looking at phytosterol consumption at two grams per day to lower cholesterol. And they found that it reduced cholesterol absorption by 25%, which is a pretty big amount considering when you and you'll learn about this on the cholesterol podcast that I've done specifically on this subject, a lot of the cholesterol that we consume is excreted, but if you can reduce the amount of absorbed cholesterol from our consumption of cholesterol by 25% as this study was looking at, then it can have a measurable impact on your overall cholesterol levels as well. It can be very hard to get two grams of phytosterols in your diet, which is why this particular study looked at enriched spreads. And just to give you some insight into how much that would be, pistachios are one of the highest. They have around 250 to 300 milligrams per 100 grams of serving. So to get the amount of phytosterols in that particular study of two grams, you'd be looking at 5 to 600 grams of pistachio alone. Like I said, phytosterols aren't just in nuts, you can get them in broccoli. There's about 50 milligrams per 100 gram serving. You can get it in carrots, 15 milligrams per 100 gram serving, corn is 70 milligrams. So you can understand the more vegetables you have in your diet, the more of these phytosterols that have this cholesterol lowering effect, you can consume a lot of these, which may have, may explain some of the benefits as well. All right. So that's number one. Nuts, seeds, try and get 30 grams a day. Number two, whole grains. So barley, buckwheat, oats, one of my favourites is Kamut, red rice, wild rice, which is slightly more expensive, beautiful grain. There was a meta-analysis of 45 prospective studies that found those with a higher intake of whole grains, around 90 grams per day, which isn't that much, had a 21% reduced risk of coronary heart disease and a 16% reduced risk of cardiovascular disease than those who ate less than 90 grams per day. So it's not that much. You don't have to have that much carbohydrate in your diet to have these potential effects. There was another meta-analysis of 25 randomised control trials that found consuming whole grains as opposed to refined grains, which is a very important point that I want to underline and bold type, improved total cholesterol and low density lipoprotein cholesterol, LDL-C. Now, carbs get a lot of slack and grains get kind of mixed up into that discussion as well. And here's why. When something is labelled as whole grain, like whole grain bread that you tend to find in supermarkets, they're generally pretty terrible because they are sometimes dyed with brown colouring to make it look whole grain. A lot of the grain itself is white and then it's mixed with something else to give it this sort of brown appeal of whole grain. And actually, if you think about the processing of bread, it's a very laborious and time intensive process. It should take days for the fermentation, the effect of soaking, there's a whole artisanal way in which we should be making bread. But supermarkets, to their credit, increasing the supply of food, has sped up the process and made what is a very healthy daily staple quite unhealthy. And that's why I don't recommend people consume wraps or breads from supermarkets on a daily because they're generally not very good for us. Most of the carbohydrates that we consume are not whole. There was another study looking at the consumption of carbohydrates in one's diet, which is around 60 to 70%, and of that, the majority of it, at least three quarters of that was processed. And so if you're consuming carbs mostly processed, it's very easy to see, and this is something that we see quite a lot online, to point the finger at carbs as a whole, whereas actually we need to be improving the quality of carbohydrates that we consume. And one of the ways in which we do that is by consuming whole grains as well. The other thing, as I've just pointed out, looking at that particular study is that overall we eat too much of the carbohydrates because they're palatable, they tend to be quite cheap, easy to consume, and these are the things that are promoted to us as well, particularly in processed forms. So crisps and packaged goods, generally long shelf life, you know, it's very easy to over consume. And I think everyone's had that experience of popping open some crisps or chips or whatever you call them in the states and just over consuming them because they are designed to be hyper palatable, really easy to consume, and they don't satiate you, which is why you tend to eat more and more and more. And that's why, that's why there is that famous line, once you pop, you can't stop. And it's very true. I mean, they're being very honest about it. You've got to give them that credit. So how do they work? So whole grains contain endosperm, germ, and bran. In contrast, refined grains have the germ and the bran removed during the milling process. And these items are a great source of fibre. They are a great source of B vitamins. They also have trace minerals such as iron, magnesium, and zinc. So you're losing a lot of that nutrition in a refined flour compared to a whole unprocessed. These dietary fibres, particularly soluble fibres that are found in whole grains from the endosperm, the germ, have been shown to bind to bile acids in the intestine that stop them from being recycled back into your system. And this is where the magic happens. Because when the liver realises that it's low on bile acids, it kicks into gear and starts producing more. And so it starts pulling more cholesterol out of circulation, out of your bloodstream, which depletes intracellular cholesterol. And so with less cholesterol hanging around, your cells start to increase the expression of LDL receptors on the cell surfaces, which act like little cholesterol vacuum cleaners, further reducing these cholesterol levels in the blood. So there's a bit of a domino effect there triggered by soluble fibres. I just want to summarise that again because I think it's a really good point and something that you can potentially talk about at the dinner table when you're scoffing down your whole grains in front of your friends or family. So the soluble fibres, they stop the recycling of bile acids. Your liver starts producing more, kicks into gear, and starts pulling cholesterol from your bloodstream that depletes the cholesterol. And with less cholesterol in your body, in your systemic circulation, the expression of these LDL receptors on cell surfaces, which are acting like vacuum cleaners, they're sucking more cholesterol. So there's less cholesterol hanging around your blood. It's a brilliant system and that's just one of the ways in which these soluble fibres in whole grains can act to improve overall cholesterol levels. So, how much? Two to three servings per day, that's all you need. Whenever you can, replace refined grains like white rice and white bread with whole grains. I'm particularly interested in grains like buckwheat because they're gluten-free, so that's a lot more accessible to people. There's also oats as well, and I try and go for jumbo oats that are organic. We've done a whole podcast episode on what ingredients I tend to choose organic more over than others, and oats is definitely one of them because they tend to be highly sprayed. Oats are getting a bit of a bashing right now because of oat milk, and I think I agree, oat milk can be very sugary because you're essentially just taking out the starches of oats and not combining it with the fibre that actually has this cholesterol lowering effect. Barley, rye, spelt, these are gluten containing, but they are wonderful sources of whole grain. They're particularly high in fibre as well. There are some protein, particularly in rye. And then the other things that I alluded to at the start, wild rice, Kamut rice, and black rice as well, also known as forbidden rice because it was forbidden to anyone to have this particular type of rice. It was only the emperor's rice. This is going back to the Chinese dynasty. Quinoa is not technically a grain, it's a pseudo grain, but a lot of people lump it in together. It's one of those novel plant-based ingredients that has all nine essential amino acids as well, which I find really interesting. And I tend to use quinoa as well. So mix it up, have that diversity, get all those different fibres and just know that this is keeping your LDL cholesterol levels low. The third thing, and one of my favourite ingredients, pulses, high in both soluble fibre and plant protein, some of them anyway. So there was a meta-analysis of randomised control trials that found that dietary pulses at a median dose of around 130 grams a day, which again isn't that much, lowered LDL-C. These reductions are consistent with the findings from two previous meta-analyses that are at a level that would be considered clinically meaningful. So this is having a clinically meaningful effect on your cholesterol levels. There was another meta-analysis of 27 studies that included over half a million people that found that consumption of just four times a week, 100 gram per day serving of legumes, so that's beans, lentils, peas, pulses, all that kind of stuff, had a 14% lower risk of heart disease. So there isn't a study where legumes have been involved or where increased fibre has been promoted where I haven't seen benefit. And most of us under consume fibre as a general macronutrient category, and legumes are a great way of trying to get those in as well. So how do these work? So there are several mechanisms that can explain this lipid lowering effect of dietary pulses. We already talked about the fact that these have soluble fibres in, so they can work by increasing the amount of cholesterol reabsorption by reducing bile acid resorption. So in a similar mechanism to whole grains, but they can also be fermented by your gut bacteria. It's, you know I was going to mention the gut bacteria at some point. I've waited to the end of this podcast to talk about gut bacteria fermentation. But essentially, legumes can be fermented by gut bacteria in the colon, which leads to the production of these short chain fatty acids like propionate and butyrate, both of which have been shown to have cholesterol lowering activity in cell cultures and animal models, as well as randomised control trials in humans. So there is definitely something going on with the types of bugs that are encouraged by consuming legumes on a regular basis. These bugs can have a cholesterol lowering effect, the mechanism of which is still being deciphered, but just know that improving your gut bacteria can have this effect that will certainly improve your cardiovascular disease, as well as brain health, as well as mood, but we're just sticking to LDL cholesterol and cholesterol in general today. Globulins. Pulses and legumes contain a specific family of proteins called globulins, and these are suggested to lower cholesterol levels in cell culture and animal studies, but the exact mechanism again by which this protein lowers cholesterol is kind of unclear for now. The other thing about legumes, and I think this is the more sort of pragmatic approach to explaining the associations that we see. This is kind of like the Occam's razor, the the simplest explanation that we have, rather than these like, you know, specific mechanisms that we don't fully understand. Is it globulins? Is it soluble fibre? Is it the impact of our gut microbiota? It's probably all those things, but the simplest explanation is replacement. So when you consume more plant-based proteins, you're having the protein from plants that is satiating. You're probably going to be having less meat or at least replacing the saturated fat that you find in most meat products, which can have a beneficial effect by just simply reducing the amount of saturated fat that you have in your diet, which has a cholesterol raising effect. So the potential benefit on cardiovascular disease may not even be cholesterol lowering, it might just be the replacement of anything that is cholesterol raising. So that's a, that's sort of like a cynic's view of looking at this to say this doesn't actually have a cholesterol lowering effect, it's just having a neutral effect, but you're replacing some of the harmful ingredients in your diet. Now, this isn't to say that people shouldn't be having meat in their diet, particularly lean meats, whether it's lean poultry, lean red meat, fish in particular. I think those do deserve a place in our diet, but this may be one way in which we're seeing improvements in cardiovascular disease with legumes as well. You also have a lower glucose spike. We've talked before about legumes and how they produce a lower glycemic response. So the glycemic response is your blood sugar response after consuming food or postprandial glycemic response. And that can encourage the liver to produce less cholesterol, less triglycerides. So there's another explanation there as well as to why it has a cardiovascular protective effect. So how much? 130 grams per day, which is about 1.5 to two servings, or four times a week, 100 grams. That's the general sort of dose range. I see a serving of beans and pulses as around 80 grams, which is about three or four heaped tablespoons of haricot beans, kidney beans, cannellini beans, butter beans, adzuki, chickpeas, take your pick. There's so many different ways in which you can explore different cuisines and recipes with these. You know, it could be an adzuki bean Japanese dessert with low sugar. Make sure that you're not putting too much sugar in that. It could be a mapo tofu, which is made with soy and black beans. Sometimes the Koreans put a bit of red meat in it. That's okay, but you're encouraging a lot more consumption of these legumes as well. I have loads of hummus-based pastes, and you can make hummus with not just chickpea, but you can make it with white beans. In fact, last night I had a miso butter bean soup with nutritional yeast blended together with a bit of hot water, and then I topped that with even more legumes. So I grated tempeh, I baked that for around 20 minutes with a little bit of paprika and cinnamon and a little bit of olive oil until it got nice and crispy, and that was put on top of the soup with a bit of greens as well. I had some watercress on the side. So I'm getting two doses of those legumes. I'm getting plant-based protein. And if I wanted to hit my nuts and seeds quota as well, just a sprinkle of pumpkin seeds on each of those. That is a really healthful recipe that ticks all the boxes for everything that we talked about today. So those are the three things I think you should be thinking about. Extra, which we're going to dive into a little bit more detail on another podcast because this is already getting a little bit too long, is spices, particularly turmeric, cumin, and ginger. So there was a meta-analysis that specifically showed turmeric and curcumin, which is a particular phytochemical that's found in turmeric. In fact, there are many different curcuminoids. Turmeric and curcumin supplementation exerted a statistically significant improvement on blood levels of total cholesterol, specifically LDL-C and HDL-C as well. Approximate weighted dose was about 2.3 grams per day. So supplemental form, but it is quite easy to get two to three grams per day if you're eating curries and different ways in which you can use turmeric. And for cumin and ginger, the evidence was considered kind of sketchy for effects on LDL cholesterol, but there was a definitely an effect that we saw in certain studies. And we're going to be doing a bit more of a deep dive into that as well.
Dr Rupy: So there you have it. That is my list of foods to help lower cholesterol and improve your heart health and probably improve your brain and mental well-being as well. I'd love to know your experiences of using food as medicine. So let me know your experiences in the comments below and we'll have a read and give us some suggestions of what other things you'd like us to discuss as well. I'm more than happy to do a deep dive into the research of nutritional medicine and I want to try and give this in the most accessible way possible.
