Dr Simon: We don't eat macronutrients, do we? We eat foods, which is why we can talk about saturated fat and cheese and we can we can start to worry about cheese, but actually cheese is much more than saturated fat. And I think similarly, you can talk about extra virgin olive oil, but actually talking about it in the context of foods, combining, and also context in the context of meals, I think is is is is really where we need to be focusing the science.
Dr Rupy: Simon, what are the benefits of having extra virgin olive oil every day?
Dr Simon: Well, extra virgin olive oil is really at the heart of the Mediterranean diet, and probably most people have heard about the benefits of the Mediterranean diet. It's the one dietary pattern that has really got so much evidence to support it in preventing all sorts of chronic illnesses, from everywhere, everything from heart disease, stroke, diabetes, cancers and and and even Alzheimer's disease. And in the Mediterranean, they consume a lot of extra virgin olive oil. And as you know, it's really challenging to actually evidence a single ingredient that makes a difference. But actually extra virgin olive oil is a bit of an exception because there are studies that show that there are associations with consuming 20, 30, 40 mils of extra virgin olive oil a day with reduced risks of stroke, of heart attacks, of of of some cancers. And also there's most recently been a study about some high antioxidant extra virgin olive oil that seems to slow the decline of people's cognition if they have Alzheimer's disease. So lots of interesting evidence really coming up about the unique profile of extra virgin olive oil.
Dr Rupy: And you mentioned two things there, high polyphenol and the dose of 20 to 30 mils. So I wonder if we could extrapolate on that. So 20 to 30 mils, that's the minimum.
Dr Simon: Well actually, actually the majority of the Mediterranean diet studies take between 30 and 50 mils. So actually it's a little bit more, a couple of tablespoons plus a little bit more. I mean actually in Greece they consume on average about 70 mils a day. So so that's a lot, a lot of extra virgin olive oil in the traditional diet. So there's there's a lot of scope to have quite a lot. But if you use it for cooking and dressing and flavouring and moisturising just throughout your day, then you can soon find you get yourself get through that kind of quantity.
Dr Rupy: Amazing. Okay. So 20 to 30 mils every day is the minimum that I want to be looking for. So it's about two tablespoons or so. In terms of how you consume that olive oil, how would you recommend people do it? Because there's lots of people online who are literally taking a tablespoon raw every day in the morning, that kind of thing. Is that the best way or is it in combination with certain ingredients?
Dr Simon: So the evidence shows that actually extra virgin olive oil really has lots of lots of power if it's if it's mixed with other ingredients. So there's some interesting studies about the exchange of antioxidants between vegetables and extra virgin olive oil, the effect of the oil if you drizzle it on a carbohydrate to slow the glycemic, slow the sugar rise. So it seems that combining extra virgin olive oil with foods is really healthy and that's how they do it in the Mediterranean. It's it's a food. Now, you do occasionally, if you're if you're on the on the going through the deserts of Tunisia or Jordan, you might see a worker on the side of the road swigging some extra virgin olive oil to give him a bit of energy through the day. And that and that's that's that's part of the tradition of many countries. There's no specific science to show that it's better on an empty stomach. But there is lots of evidence to show that it's actually great with food. And and after all, I mean, that's what enhances the flavour of food, makes the texture so much more delicious. And so I'm a great fan of of of having it with food and and throughout the day. But I don't think there's anything wrong with taking it taking it on an empty stomach as a shot as as many people are doing these days, it seems.
Dr Rupy: Yeah. And certain people are taking to intermittent fasting. So there are various regimes out there, so 14/10 or 16/8. And as a method of breaking one's fast to sort of ease your digestive system back into consuming food again, is there any evidence for taking the olive oil in that context or again is it?
Dr Simon: Again, there's no specific evidence. I mean, it is quite interesting that you see it as part of the traditions. And often, often those traditions are based on people's experience. And of course, Hippocrates who recommended that you had extra virgin olive oil to prevent ulcers, he obviously didn't do any randomized control trials, but maybe there's something in it. So so maybe there is something in in in this sort of idea of lining your stomach. But certainly, I would not do that at the expense of having it with food as well, because as I say, cooking with it and taking it with food, there's some really elegant evidence showing that there's a combination of really good bioactive polyphenol compounds mixing with those foods.
Dr Rupy: Okay. And the other thing you mentioned was high polyphenol content olive oil specifically. So how do I know which olive oil is of that category? And is there a way if it's not shown on the on the bottle to tell that, you know, it's most likely going to be high polyphenol content?
Dr Simon: That's a really, really good question. And polyphenols are fascinating. I mean, I'm glad that we're talking about polyphenols. And you know, we've started talking about polyphenols really in the last few years because we we sort of understand I think about macronutrients, you know, the carbohydrates, the proteins and the fats. I mean, we still argue about them, of course, but but we fundamentally know we should be having whole grain carbs, we should be having often plant-based proteins and we should be having sort of healthy fats, lots of minerals and vitamins from good soil, you know, well-nurtured nurtured crops. But what's now, I think really exciting is that people are discovering the very powerful effect of bioactive compounds. And these include the carotenoids, which you you get in carrots, for example, the sort of coloured coloured chemicals in there. The the sulfur compounds you get in in in broccoli and and in in garlic and so on. But also polyphenols. So polyphenols are these bioactive compounds which seem to have really powerful anti-inflammatory and antioxidant effects. And so in order to be able to know how to recognise them, it's important to understand actually what they are. And polyphenols are fascinating because polyphenols are produced by plants. And you know, I think we often think of plant, we often ignore plants, don't we? We walk past a plant, a tree and we we tread on tread on it and we don't really care. But plants are phenomenally smart. You know, I I'm I'm very privileged. I can look out from one of my windows and I can see a huge oak tree. You know, and when the going gets tough for that oak tree, it can't uproot itself. It can't go somewhere else. It can't go to the country. It can't. You know, when it snows, it's got to protect itself. When it's really, really hot, it's got to protect itself. And plants have developed polyphenols to protect themselves. So they protect themselves from oxygen. So there are polyphenols on the outside of an apple, which when you cut it open, the oxygen starts immediately to change the colour, to have chemical reactions. So protect itself from oxidation. They also protect the plant from microbial attacks, so so from infestations or infections. They also protect the plant because often they're quite bitter to put animals off eating too much of them. Yeah, yeah, yeah. And then the polyphenols are often very coloured compounds, which change in colour to signal to a mammal that the fruit is ready and mature enough to be to be to be eaten and taken. So if we hold on to a couple of those things from these really smart plants, we know that they produce them as antioxidants, just like the apple, outer outer outer cover protecting it from oxidation. And we also know that they protect them from from being eaten. So they can taste a little bit bitter. Bitter. Yeah. So when you're looking for these polyphenol antioxidants from an olive tree, you may well find that it's slightly bitter, slightly pungent in the oil. So you can taste these polyphenols. Actually, it's actually a really pleasant taste, particularly when mixed with food. Sometimes people find it a little bit needing to get used to. So you can taste it, but you can also know that it's likely to be higher in polyphenols if it's harvested earlier. Because the the the fruit needs most protection early and throughout the season until it's ready to be ready to be consumed by a bird or or a mammal. So it's about getting that early harvest. And also, because we know plants are smart, when they're stressed, when there's a challenging environment, they will increase the quantity of polyphenols in response to protect the fruit from this challenging environment. So if you have early harvest, if you have a tree that's stressed a little bit, challenged, not over-irrigated, you know, not not not over over-fertilized from a naturally going grove, they often will have these bitter, pungent, beautifully tasting high polyphenol oils, which in their antioxidant capacity, it's it's complicated the way they operate because we don't quite know for sure what happens when they pass through the gut, you know, and the gut microbes and so on. But but actually they have an antioxidant effect in our bodies as well.
Dr Rupy: Gotcha. Okay. So I'm taking early harvest as a as a label that I should be looking out for. With regards to the stressing of the crop, should I also be looking for things like grown at high altitude or organic, for example?
Dr Simon: Absolutely. So there is some evidence, it's quite limited evidence, but there is some evidence that the polyphenol content in organically grown crops is higher. Absolutely. And similarly, at a bit of altitude. So at a little bit of height, or perhaps on the on the side of a of of a mountain, you can imagine it, can't you, in in Greece. Yes, at altitude. And and olive trees can grow up to 700, 800 meters, sometimes a little bit higher than that. And they and they they they flourish there, but they do they're more stressed actually by the the UV light. And so and so they can produce more more polyphenols. Okay. And so yes, a sort of high altitude and sometimes people mention the producers mention this on their on their labels, which is always good good to see.
Dr Rupy: And what is a decent polyphenol amount in milligrams per litre of of olive oil I should be looking for?
Dr Simon: Yeah, so the what is high polyphenol is actually defined by the European Food Safety Authority because they've actually allowed a health claim on extra virgin olive oils that contain a particular minimum level of polyphenols. And high polyphenol levels are anything above 250 milligrams per kilogram. So that's the measurement. And and you do get some oils, you get many, many oils which are likely to have much, much lower levels. And they won't pass the EFSA regulation which says that you're allowed to say state a health claim on the basis of those polyphenols. There are some oils that are being promoted for being super duper ultra high polyphenols. And and that's fine on on one level, but they can become really quite bitter and really quite pungent. And so occasionally they're marketed actually as medicinal. So in in small in small bottles. But the reality is that we don't actually know what the right level, I mean, we know a good level is above 250 milligram per kilogram and and that's what the science is showing demonstrating these antioxidant effects. But we don't know if you get much higher whether whether well, even whether they have the potential to do harm. Because there are, of course, investigations of other antioxidant compounds which have shown that actually by supplementing with very high levels of antioxidants, there was an experiment, wasn't there many years ago, using vitamin E for for lung cancer, and actually it showed that it probably turned off our own internal innate redox, which is our antioxidant mechanisms. I I would say above 250 milligram per kilogram is a good level of of of polyphenols. And maybe these ultra high ones, I would be a little bit a little bit cautious about saying, certainly there's no evidence that they're any better. And we just don't really know what what they're doing at that kind of level.
Dr Rupy: Yeah, I think it's a really good point because more is not necessarily more. And I think with most things, food included, but certainly in medicines, you want to make sure that you're getting that therapeutic window. And the dose of polyphenols in this case is probably, there's probably going to be a normal distribution whereby you're having like an ideal amount at a certain level that sounds like it's going to be above 250, but perhaps not much higher than, I don't know what the upper limit of these products are, but you know, 700, 800, maybe, I'm not too sure. But that might have a damaging effect whereby the antioxidant effect is so, so high, it can destruct your internal antioxidant mechanism.
Dr Simon: Yes, I think that is a possibility. And actually the power of polyphenols can be demonstrated by what I call the kudu story.
Dr Rupy: The what story?
Dr Simon: The kudu story.
Dr Rupy: The kudu story.
Dr Simon: So we've been talking about smart plants producing these polyphenols to protect themselves from from the environment, whether it's oxygen in the environment, whether it's UV light, whether or not it's, you know, being being being eaten before the seed is mature. And and the kudu story is a story about kudus in South Africa. Kudus are are wonderful, graceful antelopes. And there's there's a story that that suddenly a few years ago, it was noticed that on some of the game reserves where they had high concentrations of these beautiful antelopes, they were dying. And they were just just literally falling down dead. And nobody quite understood why. And it turns out that when they took them back to to the to the University in Pretoria and and did post-mortems, they discovered that they had toxic levels of a polyphenol called tannin, which, of course, tannins we get in tea and we get in we get in other wines and so on. Transpires that the kudus were eating acacia trees, but there were so many kudus, the acacia trees were realizing they had to control the kudu's numbers. So they would produce under this stress, toxic levels of of of of so so if you're a kudu and and you're and you're eating an acacia plant, you've got to be warned because, you know, they can they can live nicely in harmony, but these smart plants can actually produce toxic levels. And you know, the other fascinating just little little note at the end of that story is that we're now beginning to understand that plants can communicate with each other.
Dr Rupy: Oh, via the microbial network?
Dr Simon: Yes, and also by aromatic compounds that are exchanged. And the fascinating sort of um um uh final chapter of the story is that they looked at all the acacia trees that were ratcheting up their levels of of polyphenols to protect themselves. And um they saw that outside the game reserve, beyond the fence, the acacia trees were also having toxic levels of tannins. So they were communicating despite the fact that the to warn the other trees to increase these levels of tannins, despite the fact that the kudus actually couldn't couldn't get out of the game reserve.
Dr Rupy: That is mind-blowing.
Dr Simon: Which is quite extraordinary, isn't it? So whenever you have, because we digress sometimes, but whenever you're consuming an extra virgin olive oil and it's quite bitter, quite pungent, I mean it's softened when you add it to a salad and and the tastes are really, really, really beautiful. You can think about those compounds just produced for that little bit of bitterness and pungency. And you know, in we've enabled, we're pressing the olive, the very, very bitter or or actually um um making it into olives by by some processing, fermenting, we've actually managed to get these concentrated polyphenols into our diet in the form of extra virgin olive oil.
Dr Rupy: Yeah, that's fascinating. We we mentioned polyphenols quite a bit now. And I I wonder if, I mean, there are thousands of different polyphenols in existence. Only a a few of which have been studied in much detail. Are there particular standout uh polyphenols that we find in olive oil that have been studied a bit more detail that might explain some of these effects on on heart health and so on?
Dr Simon: Yeah, you're absolutely right. I mean, there are over 8,000 polyphenols that have so far been identified. More than 36 in extra virgin olive oil. And the interesting thing is that many of them are really very unique. So you get a lot of similar um um similar polyphenols in blueberries and in grapes and and wine and and so on, which all potentially have positive anti-inflammatory and antioxidant effects. But the ones in extra virgin olive oil, many of them are actually quite unique. Um and um so we talk about polyphenols like tyrosol, hydroxytyrosol, um oleuropein, um we talk about oleocanthal, which is the one that makes you cough slightly. Which which is very powerful anti-inflammatory. Um and so yes, there are some very unique ones in extra virgin olive oil.
Dr Rupy: Yeah. And the fats that we find in olive oil, mostly monounsaturated fatty acids, I'm guessing, but there are some poofers there because there's, am I right in thinking that olive oil is a good source of the short chain omega-3s?
Dr Simon: Yes, but but but it's mainly monounsaturated fats. So it's mainly mono and many oleic acid, which is the the the monounsaturated fat named after after the the olive tree and and and olive oil. So it's mainly monounsaturated, some, as you say, some polyunsaturates, um and a little bit of plant-based saturated fats. Um but predominantly monounsaturated fats. But it is thought really that although the monounsaturated fats, you know, we know can support healthy lipid levels, healthy cholesterol levels, actually the really interesting thing is going on with these polyphenols, which actually comprise a tiny percentage of the olive oil, but have really important uh effects despite the fact that they're in relatively low low concentrations.
Dr Rupy: Gotcha. And the anti-inflammatory effect of these polyphenols, is that what can potentially explain the beneficial impact on lipid ratios? So things like LDL cholesterol, total cholesterol, apolipoprotein B, is that from the anti-inflammatory effect of olive oil or is that still sort of a bit of?
Dr Simon: I think that's the fats acting on the but the important thing about fats we're now understanding is the level of oxidation of fats. So again, that's really important, which is that we might have an LDL, we might have a level of LDL, but actually the harm is really going to come when it oxidizes. So when it's oxidized. And the interesting thing about the European Food Safety Authority health claim that's allowed on an extra virgin olive oil with a particular minimum level of polyphenols is that it talks about reducing the ox LDL, the oxidative stress on the LDL cholesterol, which is what is part of the inflammatory process that we now know contributes so much to to to to heart disease. So it's it's so so that element to it is really important. The the inflammation related to the development of of of of heart disease.
Dr Rupy: On the subject of oxidation, heating olive oils. So this is a common question that we get about whether we should be using good quality olive oil or high polyphenol olive oil to cook with or whether it should be used as a finishing oil or whether that, you know, it should not be used at all in any amount of heat. What what are your thoughts on that?
Dr Simon: Yes, so my thoughts are that first of all, extra virgin olive oil has been valued and has been used in the Mediterranean for millennia. And it's been used, I mean, they obviously didn't have the facilities to produce the quality that we can see today, but they would be they would be valuing these bitter and pungent oils. And of course, the Mediterranean diet, they don't use anything else for cooking. And so in some respects, the Mediterranean diet couldn't work if it was unsafe to to use. And there's some now evidence which which nicely backs that up because it's demonstrated that people talk about a smoke point, which is the the point at which an oil begins to degrade or change. And there are several things to say about that. First is that the smoke point of a good extra virgin olive oil with some polyphenols to protect it from the oxidation that goes on when you're cooking and the breakdown of the fats. Um the the the smoke smoke point is about 200, 210 degrees centigrade. And of course, we normally cook well below that temperature. And the other thing is that actually it's much more important to look at how a an oil performs over time. So we should be talking about how what happens when you cook at normal temperatures for perhaps 20 minutes, 40 minutes, or even several hours. And there's some studies from Australia which actually showed that if you're cooking at 180 degrees, I mean, they actually heated the oil to 240 degrees first and then reduced it back to 180 degrees for six hours, comparing different oils. The oxidation, the trans fat formation was higher in other oils. The um the the the number of antioxidants left at the end was highest in extra virgin olive oil, partly because it starts off with with so many of these of these antioxidants. And the formation of polar compounds, which are these sort of chemicals, the charged chemicals that are produced when an oil when a fat breaks down, um these polar compounds which we are concerned that some of them may, you know, may cause cancer, may be carcinogenic, they were significantly lower in the extra virgin olive oil. So those kind of experiments cooking seem to show it's absolutely safe, but but also advantageous in comparison with other with other oils.
Dr Rupy: Yeah. And I think the more experiments we can do with cooking oils that actually are a lot more practical and they have practicality baked into the research methodology, the better because that's something that I intuitively understand now, like, yes, you can have a higher smoke point for perhaps some other oils, but how are you using that oil over time? How you're how long you're cooking it, sauteing your food, etc. That's probably going to have the that's the most important factor to consider.
Dr Simon: Yeah, and I think you you'd know if you were pushing any oil to an excess heat because it starts to blue smoke starts to it tastes horrible. And and you wait for it to cool down and then you throw it away feeling relieved that you haven't had to call the fire engine. And then you'd go back and you'd start and you and you'd be paying more attention. So so actually we don't tend to smoke oils, we don't tend to burn them. And I think you're right as well that it's about when you cook things together because I'm always very conscious that we don't, you know, we don't eat macronutrients, do we? We eat foods. You know, which is why we can talk about saturated fat and cheese and we can we can start to worry about cheese, but actually cheese is much more than saturated fat. And I think similarly, you know, you can talk about extra virgin olive oil, but actually talking about it in the context of foods, combining, and also context in the context of meals, I think is is is is really where we need to be focusing the science because because we know that the effects of of of eating foods are not in isolation. It's in the context, it's in the food matrix, it's what happens when it hits our trillions of uh of hopefully friendly gut bacteria. And and so it's much more complicated than that, isn't it?
Dr Rupy: Is there an effect on uh on our microbes of olive oil?
Dr Simon: Yes, absolutely. I mean, if you look at different diets and their impact on increasing the the the diversity and increasing what we know to be the bacterial species that have a beneficial effect, you can test that with the Mediterranean diet and particularly with with extra virgin olive oil, you know, absolutely at 30 to 50 mils a day, whatever. And you can demonstrate some really quite rapid changes to people's um to the diversity and health uh of their of their gut microbiome. So so, you know, not many of us, I mean, maybe you do, maybe I do, but not many of us wake up in the morning and think, what are we going to feed our trillions of gut bacteria? But I can tell you, we should be getting up and thinking, what am I going to feed my trillions of of gut bacteria on today? Let's get them on some Mediterranean diet. Let's let's give them give them some really, really great, healthy, high polyphenol, plant-based foods.
Dr Rupy: Absolutely. Absolutely. And actually, because you've written this wonderful book on diabetes, that was going to be my next question. Is there are there some, I I certainly see the appeal of uh a Mediterranean diet when it comes to improving management of type two diabetes in particular, uh pre-diabetes, maybe even staving off diabetes before it gets to that established type two diabetes diagnosis. Are there things that olive oil are doing within the context of that Mediterranean dietary pattern for for type two?
Dr Simon: Yeah, absolutely. Um olive oil for a for a start, I mean, like other fats, when you put it on a carbohydrate, it decreases the glycemic rise. But there's also some really interesting evidence coming again back to the polyphenols. They seem to be able to increase insulin sensitivity. So there's a there's there's there's some suggestion that that extra virgin olive oil as a as an ingredient within the healthy Mediterranean diet actually can have a beneficial effect um on insulin sensitivity. But when my my um writing this book with my with my co-author, um Amy Riolo, who's who's based in the US, um what we were really keen to do is is take the debate away from this issue about carbohydrates, just about carbohydrates, because really, I think we need to be talking about foods and I think we also need to be talking about dietary patterns. And the thing for me about about about diabetes and and you know, having been in practice, is that the complications of diabetes are what really cause people the problems. So the heart disease, the stroke, the cancers. And so what worries me sometimes is that people are looking at dietary dietary methods to fix diabetes without actually looking at what these diets are potentially doing on all the diseases that are the outcome of poorly controlled type two diabetes. And the great thing about the Mediterranean diet is we know that not only is it helpful to reduce the risk, prevent, um there's there was a research paper that I saw published today showing long-term follow-up of people, um people who started off as students in terms of their risk of developing type two diabetes, dramatically reduced on the Mediterranean diet. And yet it's also such a diet that's really, really helpful for all these other conditions that are related. So you get real bang for your buck um if you have the Mediterranean diet. And and so not surprisingly, um it's been voted by the US News um um um annual survey to be the best and most recommended diabetes diabetes diet, being very conscious of your carbohydrates, of course, um but you know, having a having a good quality Mediterranean diet is is really positive for for diabetes.
Dr Rupy: Definitely. In terms of um where we source our olive oil from, I'm aware of the producers, particularly from places like Greece, for example, Spain. Um are there other are there other novel producers of olive oil that are of really high quality that we should be looking out for?
Dr Simon: Yeah, absolutely. I mean, it's quite interesting because you can um you can grow the olive tree where you can grow vines more or less. So it's on the sort of 30, 40 degree parallel north and southern hemisphere. And extra virgin olive oil is best fresh. So there are two harvest seasons, the northern and the southern hemisphere. So the story of of of the olive tree is a wonderful story because of course it started off as a wild tree in the Levant, in Iraq, Iran, Syria, um cultivated in the fertile crescent, first agriculture, cultivating olive oil. Phoenicians probably bringing it across to the Mediterranean, the Spanish ports and and and and and North African as well. Um and then of course with the with the discovery of the Americas, um the the the Spanish and the Portuguese took their their most valued um possessions over there um and started planting trees in fact in in Peru and Chile to begin with. Um and now there's a there's a great industry in in Peru and and Chile and and Argentina. Um and then of course it went up to California. And so we've got Californian oil as well, a bit in Florida. So it's it's in the in the new world, um in the northern hemisphere and the southern hemisphere. And then in about 1600, 1650, the Dutch were were were travelling around the uh the the the South African uh cape to get to the to the East Indies. And uh so they planted olive trees. Um although they weren't very successful at that time, but they've now got a flourishing South African. And I had the great privilege of um being uh visiting a grove in Australia where they've planted since the 1990s um on land that wouldn't sustain wheat now because because of global warming. And they've they've planted, you know, hectares and hectares of extra virgin olive oil. So it's it's it's it's spreading, spreading its roots throughout the world actually as people recognize it's a really healthy, really sustainable because for every litre of extra virgin olive oil on a well-managed grove, you sink 10 kilograms of.
Dr Rupy: Oh, you just okay, that was going to be my next question about sustainability.
Dr Simon: Yeah. And so it's a really sustainable crop. We know the Mediterranean diet is really sustainable because it is fundamentally a vegetable high diet. Um um and you couldn't eat, you know, you couldn't consume so many vegetables if you didn't have extra virgin olive oil to do with them.
Dr Rupy: And in terms of the other oils that are available, um I'm thinking particularly of avocado. Um I mean, there's so many other oils out there. There's mustard oil, all the rest of it. How does how do they all rank in terms of quality as we could judge them by polyphenol content and, you know, the magnitude of effect on health outcomes? Um but also the utility of them, how we would tend to use different oils and whether olive oil can be used universally or whether there are other use cases for for other oil types.
Dr Simon: So that again is a really good question. I mean, I think there are often places for all of these oils, particularly because they often come from traditional diets, heritage diets of countries that we really haven't explored yet in terms of the health benefits. So um so we know a lot about the Mediterranean diet, but I think we also need to have a lot of respect for traditional diets of Asia, of Japan, of of of of the southern southern America. Um and so it may well be that there are some benefits of some of these natural traditional oils that have been that are yet to be to be recognized. I mean, there are some oils that are definitely not on my shopping list. Um you know, so palm oil is not it's a recent invention. And of course, even with a supposedly sustainable planting, you know, it it it there is an issue with that. So there are some oils. And many oils are refined. And so what I think you can you can you can say is that if you have an avocado oil, um I mean, it might say cold pressed extra virgin, which which means nothing. It's simply it's entirely marketing. It's not regulated in the same way that extra virginity is in the olive oil. I mean, so it's it's for marketing purposes, which is which is okay. I mean, um but you know, that's probably got, you know, a good level of of of of bioactive compounds in it. But there are refined oils. And these are oils that have been taken to a to a refinery, um heated, purified, um and um and then they are pretty much devoid of these polyphenols. The polyphenols are pretty much taken out by chemical and heating processes. So things like canola oil, the vegetable oils. And in fact, actually the the the the we'll we'll talk later about these different extra virgin olive oils, but we've got an olive oil over there. And it's important to understand that olive oil is a refined product um without being without passing the standards of extra virginity. They take defective oil often and take it to a refinery and process it heavily. So it's it's it's it's a fat, but that's more or less all that you can, I mean, it's a monounsaturated fat, but it hasn't got these rich, rich um polyphenols in it.
Dr Rupy: Gotcha. Okay. And out of the oils that you might find in, you mentioned like Japan, Korea, uh Southeast Asia, I'm thinking of. Um do we know anything about the potential benefits of those oils? I'm thinking of like sesame oil or.
Dr Simon: So I think the answer is we haven't we haven't really studied them as much. And certainly, you know, we have we're very orientated, I think in in terms of in terms of a a sort of um Western view of of the world. And and maybe we should be reorientating ourselves and and actually, you know, just being more interested. The Mediterranean diet is a much studied diet and it is, I suppose, a heritage diet of the of the people of of of the Mediterranean and and beyond. Um but I think there's, you know, lots of reason to to to suggest that that that that other traditional and heritage diets are studied because they have many features in common. Um and the oils may be slightly different, but they have other features in common, um often with some parallels around high consumption of beans or or or or high consumption of of fruit and vegetables. So, um I think there's lots of exciting, potentially more polyphenol stories to tell from other heritage diets.
Dr Rupy: For sure. Yeah, yeah. No, I'm really interested in that because I'm not aware of as much research or as much attention being given to other traditional oils at this point. I mean, I certainly know that coconut oil, for example, is devoid of of any uh polyphenols per se. I I can't think of any to my head. It's just a unique type of fat, would you say?
Dr Simon: Yes. And I mean, I think um coconut oil was was was went through a it's moment of glory. It was very trendy, wasn't it? It was a superfood. And we all know the definition of a superfood, don't we? A marketing hype. Yeah. A superfood is a food with a publicist. Yeah, yeah. As my friend uh Ian Marber says that um yeah, so um yeah, so so so yeah, not the kind of polyphenol story that you can get um in extra virgin olive oil. You know, and and the polyphenols in extra virgin olive oil possibly are really a very, very significant driver of the of the of the value of the Mediterranean diet as a whole. Um so, you know.
Dr Rupy: Okay. Um you mentioned refined oils. I think we perhaps we could have um defined exactly what we mean by extra virgin, virgin, and then olive oil, because these terms, I think are bandied around quite a bit, but maybe there's a bit of confusion as to what they all refer to, particularly in the world of olive oil. And because that was news to me about avocado not actually having a standard of extra virgin versus just regular avocado oil. So it's all the same. So what what are the differences between extra virgin, virgin, and olive oil?
Dr Simon: So because olive oil and extra virgin olive oil in particular, the one that tastes fruity and bitter and pungent has been valued for millennia, there's always been issues of of potential fraud with it. And so, I mean, even the Romans, you know, the Rome was built on seven hills, but you know, there's an eighth hill, which is called Monte Testaccio. And it's basically a Roman rubbish tip. And it's a hill and it's got amphorae, you know, these containers of olive oil and wine. And it's quite interesting because there are stamps of olive oil producers on many of these amphorae because obviously the Romans realized that they had to make sure they knew where their food came from. They had to know that it was really the real deal. And if you put your stamp on it, you know, and it wasn't the right stuff. So um so there's been there's been issues with whether whether it it's a really good quality olive oil or not. So it's now one of the most heavily regulated food production systems actually in the world because in order to carry the extra virgin label, it needs to pass two tests. Each producer has to send it send their oil to for chemical testing. And that will give you an element of, it will give you a measurement of the acidity. Now, it's not like that doesn't mean a pH, that doesn't mean a sourness. You can't taste it. What the acidity level is is the amount of the fatty acids which are normally held together in threes, as you know, with the triglycerides, the amount that have broken off because of oxidation and because of breakdown of the oil. So if they break off, they express their acidity. So you have to have an acidity level that's low to show that the fats are preserved, haven't been oxidized in the process of of harvesting and of milling and and producing the end result. And so for extra virgin olive oil, that chemistry has to show that the acidity is less than 0.8%. For virgin oils, which we don't see many of, that goes up to that's allowed to be up to 2%. You don't tend to see virgin oils um really marketed. The second test is the organoleptic test. The sensory test, or you and I would say the taste test. So um the International Olive Council has um I mean it's enforced regionally, but there are panels of tasters who will taste all these extra virgin olive oils and show hopefully that they pass not only the chemical standards, but also the taste standards, which are that they should have fruitiness, some bitterness and some pungency. And they should be without defects. And defects are when you can test that an oil is perhaps going rancid, oxidized, broken down. Um there's also other defects like mustiness, fustiness, winey, vinegary and and and mouldy. So there's lots of um so there's lots of defects you can taste. And so then hopefully, if you're if you've just produced, you're a proud farmer and you've just just produced your extra virgin olive oil, hopefully those tasters will come back uh and say, yep, passing the the taste test as well. And if, well, maybe towards the end of the season, you're getting really late harvest and and you're and you're picking up the olives that were not really selected to be the best. Um you might produce oil that doesn't pass that extra virgin standard. And what you would do then is you will sell it to a refinery. And then the refinery will say, okay, well, this is, you know, clearly defective oil, so it's not extra virgin. And then they heat it and they process it, um and they make it into a colourless, tasteless fat. And then they put about 10%, 15% extra virgin olive oil into it to give it a bit of taste of olive oil. And then they market that as olive oil. So but by the time you've heated it up, it's got a bit of vitamin E left in it, but frankly, the polyphenols are pretty much all gone. So so that's that's the definition of extra virgin olive oil. And and you know, one of the most bizarre things I've seen is is is is Italian police tasting. There's a there's an there's a uniformed brigade of Italian police who sit there tasting because there have been some episodes of of of fraud. Um and and the Italians, you know, are onto it in terms of actually trying to make sure that this is discouraged. And so they have panel taste tested and certified police who will go and investigate whether a an oil is being passed off as as extra virgin and whether it's not. And of course, it can either be passed off as extra virgin when it hasn't met the standards. Or alternatively, it could be actually adulterated, which which is in fact, I mean, you know, that's not just ripping off the consumer, but that's actually potentially really dangerous and potentially poisoning the the customer because there are some stories around some poisonings way back 50, 60 years ago. Um and then the other thing about extra virgin olive oil that you've just got to be slightly careful of is that if an oil, extra virgin olive oil is produced maybe by one of the big producers who's buying their olives as a commodity from anywhere they can get it towards the end of the season, bringing it over to a a big production plant, maybe in Italy, perhaps, using that just about extra virgin olive oil, but end of the season, lowest prices, then it might well pass extra virgin standards because it's quite mild and bland, not very many polyphenols in it because it's the kind of commodity end. It's been bulk shipped, if you can imagine these ships coming across from Tunisia or from from Algeria or Morocco. Um it may go out of that Italian um place, production site, and it may well have an Italian name, may well say product of many countries. It may go out of there extra virgin olive oil, but once it's been sitting in a warehouse, once it's been on a supermarket shelf, it may only have have only just passed those extra virgin standards when it went out. But by the time you get you get it in your in your kitchen, it may no longer have those those those qualities. It may even be potentially rancid, particularly if it's late in terms of its its best before date, because it's always best to consume extra virgin olive oil early and fresh. So so there are various bits of the market, including bits of the extra virgin market.
Dr Rupy: Yeah, yeah. And in terms of, I think we're going to get to that when we come to tasting, but if I'm looking at a bottle and it's, you know, early harvest, it's high polyphenol, but it was actually collected a couple of years ago, does that affect the quality of what's in the bottle today? I.e. is there a degradation that occurs over a certain amount of time that we should be aware of?
Dr Simon: Yeah, absolutely. I mean, the the enemies of of extra virgin olive oil are the enemies of the olive fruit, which are and not so much infection because you don't tend to get that in the bottle, but um are oxygen, heat and light. And so with and that's why many bottles, not all bottles, but many bottles are are protected from the uh from from the light by being dark bottles. Um and then over time, there's a degradation, consumption of the antioxidants, the antioxidant levels will be going down and the likelihood of the oil being rancid, defective, no longer extra virgin increase. And and so it's always good to see on a bottle the producer. You know, in some way expressing themselves and expressing their passion. It's always good to see a harvest date. The best before dates, you know, you can put a best before date of about 18 months on on an oil because it will it will keep. But to be honest, if you want to have the best, best tasting, the ones that are likely to be highest polyphenols, it's great to get a really early harvest, but but this season if you can.
Dr Rupy: Yeah, gotcha. Yeah. I mean, I guess if you're going to be having 30 mils of extra virgin olive oil every single day and there's two of you in a household, it's going to last about, you know, a couple of weeks. So you're going to be going through olive oil pretty quickly.
Dr Simon: Yes, yes, you will. And um um and that's how, you know, the Greeks and the and the Spanish and the Italians do it. Um and um you know, and it it it it may well be contributing to their to their longevity. Um and so I think the conversation about price is really important. Um and I think to some extent it is about about the choices we make because I think if we regard it as being a commodity, if we even regard extra virgin olive oil as being just another another commodity, another vegetable oil, then we may get away with with with with spending less on it. But on the other hand, if we pay a little bit more, get a higher quality, not only does it taste great, but we know that it's got these associations with with with with health. Um actually, if we just figure out where we where we spend our 10 pounds or our 12 pounds, you know, in some respects, if we went out and bought a a bottle of uh bottle of wine or if we or if we went to a a a coffee uh uh shop on our way to work, we could soon be spending um five or or or 10 pounds. And so I guess, I mean, I think we, you know, we in the UK are quite famous for spending a very small proportion of our of our of our of our household income on food. And so maybe it's about thinking, well, what am I getting for my 40p a day, you know, for a 10 pound, 10 pound bottle of of extra virgin olive oil. And for special occasions, just like you might have a a rather nice bottle of wine that that you're that you're saving for special occasions, you know, have a have a really nice premium bottle and um and have that on the table or take it as a as a as a gift if you go around go around to dinner with somebody. So I think um it's about trying to work out the economics of it, um but also valuing it as a as a really extraordinarily healthy product and and a product that is produced with a lot of costs associated because it's not easy to produce olive olive oil. It's it's it's a tough, it's a tough thing to produce extra virgin olive oil because it's not an industrially, in general, it's not an industrially produced product.
Dr Rupy: On the subject of refined uh olive oils that we were just mentioning earlier, um there's a lot of talk these days about seed oils in general about how they're harmful. Now, I can understand that you're not getting the benefits of extra virgin olive oil if you're opting for an olive oil because they're heat treated, the polyphenol content is likely to be very low, minimal amounts of vitamin E, all the rest of that. Um but are there any disadvantages apart from the absence of this polyphenols that you're introducing into your diet, any inflammatory effects by consuming that kind of olive oil?
Dr Simon: So you're absolutely right, you won't get the polyphenols in there. You'll get a high proportion of monounsaturated fats. Uh and and and those are generally regarded as being being beneficial. Um the debate about vegetable oils and some seed oils is about their levels of omega-6 polyunsaturates because in our diets, we we consume probably an excess of omega-6s in comparison with omega-3s, which are present in some some seed oils like like flax oil. Um but in general, we probably are getting that balance because of actually because of processed foods and because of baked foods, we're getting uh omega-6s perhaps in in in to too great a concentration. But I think in some respects, you know, one can talk about the the the those different proportions, but I think for that kind of debate, we need to be looking at the whole diet. And I think we need to be looking at the sort of fat distribution um and our processed foods and the other foods that contain contain these these these omega-6s. For me is is is the feeling. But I can certainly the anti-inflammatory effects, whether or not the omega-6s are pro-inflammatory, which is which is some of the where some of the concerns lie, certainly the anti-inflammatory component of the polyphenols in extra virgin olive oil is something that I think is is is, you know, beyond doubt really, really um beneficial.
Dr Rupy: Yeah, yeah. I think a lot of people get, it's very similar to what you were saying earlier about getting fixated on one element of the diet rather than actually looking more holistically about what you're eating two or three times a day, how you're living your life, how you're exercising, how you're moving, how you're sleeping, um rather than, okay, I've got to strip all uh extra seed oils that are inflammatory out of my diet because of the, you know, the effect that it might be having. I think that you should stick to the the biggest levers on the health effects of your diet rather than those individual uh elements. And there there is a bit of a debate about that, but I I think there's also a bit of fearmongering as well, so.
Dr Simon: Yeah, I think that's right. It's about striking the balance, isn't it? And I think it's also about for me, it's about positive nutrition. It's about telling telling the stories about when foods can be really good for you and really healthy. And then actually, if you focus and think about the foods that are really good and really healthy and really tasty, then actually you find yourself automatically leaving some of the really not very nice stuff behind. And even though we seem to be hardwired to to to to look for high sugar and and and high fat tastes and and perhaps as children, we're we're we're hardwired to avoid bitter because of the possibility of potentially plant poisoning. And we're introduced by our parents to broccoli, which is which is safe, but we still might not like it. Um and um and so so it's about telling those those those positive stories about actually how we can we can get away from that that that addiction. There's a debate about whether or not it's a true addiction, isn't it? But the sugars and the highly processed foods. Um but actually, you know, you can find that if you if you like chocolate, for example, I know you you've recently been talking about chocolate. But but um for me, there's nothing like a a square of really intense, really dark chocolate. And particularly with an espresso. And and it's that bitterness that I think we've lost from our taste lexicon. Um and if you if you if you really are keen on really high sugar um um um then try, you know, just just increasing the amount from 50%, 60%, 70%, 75%, 80%. And and you'll find that actually over weeks, and again, this has been shown by behavioral scientists to be true, that over weeks, you can reduce your craving. And then when actually you you you you find yourself having to eat an Easter egg that you've been given, you find it's far too sweet. And of course, the same is true of salt. You can wean yourself off salt, herbs and spices, part of the Mediterranean diet. Again, rich, very concentrated polyphenols, particularly when mixed with extra virgin olive oil, they seem to release the polyphenols when you eat them. And uh there's some great stories about herbs and and extra virgin olive oil. But you're weaning yourself off sugar, you're having lots of antioxidants from herbs and spices, salt rather. And then you go into a fast food joint and you have their fries with with with with with salt and it's just too much. It's too salty. And so I think we've got to train people and and I I have the privilege of talking um doing the health modules on some olive oil sommelier courses. And sometimes people start off and saying, well, but how can bitterness and pungency in an oil be be be attractive? You know, and I say, well, it's about your tastes and it's about your perception of taste. It's about the interest of the taste. And I say and often they they're from the states or from from other countries. And I say, well, I'll tell you what, after we finish this long day of tasting lots of lots of olive oils, let's go down, have a pint of bitter, which is bitter. Fantastic. And let's go down to the spice palace, which is spicy, and have a really nice spicy meal. And yet, we seem to have a sense of of of we sometimes don't don't want to to to have those kind of flavours. But they really are what makes food, I think, really interesting and also really healthy.
Dr Rupy: Yeah. I think the more I've gone on my personal journey towards embracing healthy foods into my diet, the more I have a deep appreciation for bitterness to the point where the chocolate I choose is 80 to 85%. The coffee I drink is black coffee, usually uh with without milk or anything. You know, the the ingredients I have on the sides of my dishes are always bitter greens, mustard greens, you know, horta of foundation of the Greek diet. Um and the olive oil that I appreciate is the real pungent, bitter notes that I think we're going to enjoy in a second.
Dr Simon: And and going back to the to what we were saying really right at the beginning, you know, these bitter notes are actually indicative of these plant plant polyphenols, um which which in small modest amounts, um in good quality foods can be really healthy for us and act as antioxidant and and anti-inflammatory compounds.
Dr Rupy: Epic. Well, I think we've convinced everyone that they should be having olive oil in their diet. I think we should move on to the more practical elements of tasting said olive oils and trying to give people um some ideas uh of how they can choose the best olive oils. The labels they should be looking out for. I know I'm now looking out for early harvest. I'm going to be looking at the when this was produced, a bit of a story about the producers is always a good thing. Um but yeah, let's go through some of the criteria. So we've got some olive oils here that we're going to try.
Dr Simon: Yes. Well, and so because we must so this is this is olive oil over here which which which you've got, which is the this is the refined product. Um so frankly, it doesn't matter that it's in a clear bottle because it's got no polyphenols in it. So so um it it it will go rancid probably quite quickly, but and and it's it's it's it's not a desirable um um oil in in in my view. Um you've got some other oils over here which we're not going to taste, but which are which are super oils. I think I've tasted at least three of them. Um uh this is Leah, um which is which is a beautiful oil from the Peloponnese um in Greece, produced by a lovely lady called Christina and her family. And um that's a yes, that's an oil, Zaytoun from from Palestine. Um and it's they very much focus on the story about it being a fair trade product. Um obviously, you know, in the current climate really potentially really struggling with that. Um this is an oil um from uh Belazu, um who are a good company actually in West West London who produce a lot of uh a lot of Mediterranean style goods. And that's a Cornicabra from Spain, if I'm not mistaken. Oh, nice. Yeah, yeah. Um and again, it's got a It's got the tasting notes. It's got tasting notes. Yeah. I can't see the polyphenol content per.
Dr Simon: No, many people don't put a polyphenol uh level on their oils. Um the Cornicabra variety, because we didn't talk about variety. Variety also influences how many polyphenols they have. And so Cornicabra, for example, is um a uh Spanish um uh oil variety which has um quite high polyphenols um to begin with. Um and a lot of Greek oils have Coratina, which again is is quite a high polyphenol. You can also get some Spanish oils which are milder. And and some are really, really very good. So there's a variety called the Arbequina, which can produce some beautiful, beautiful soft oils, probably slightly lower in polyphenols naturally. But you know, if you're if you're consuming good quality extra virgin olive oils, you know, you will probably get your your polyphenols, you know, if if you have enough of it. And um so some some great milder oils which are good for fish or good for salads. Um and then the more robust oils, um you know, like the Cornicabra, which will be a quite a robust oil and the and the and the Leah again, often uh you know, a lot of flavour to those, which might be good for um you know, good good for for for cooking vegetables, cooking meat and so on.
Dr Rupy: I thought I recognized Coratina. That's so this is from Two Fields. We we got sent this um by a friend of ours, a friend of the pod, Karen O'Donoghue, who's a a baker in um uh West Ireland. And yeah, she's phenomenal. She she asked us to try this.
Dr Simon: And I mean, I love these stories. I hope people connect. People fall in love with with with and they get a connection either through family or or they have somebody they know and they they visited and then they become very loyal to those brands, which is fantastic because actually, you know, that that's that's what it's all about. And and the producer, you know, I'm sure of that of that oil will be, you know, incredibly proud of what they do and what they produce. And so, um you know, I think um you know, apart from the the refined olive oil that we've got over in the there in the corner, I'm sure all of these would um you know, would taste taste really, really, really lovely and have different tasting notes. But we're just going to taste a few.
Dr Rupy: We're going to taste a few. So what I you asked me to get the Filippo Berio extra virgin olive oil. I think this is probably the most ubiquitous in all supermarkets. Everyone will have access to a bit of Filippo. Um benefits, disadvantages?
Dr Simon: Yeah, so I mean, I think I I think every every extra virgin olive oil has a place. And as an introduction to extra virgin olive oil, people might be taking a a bottle of this because it's familiar, because they do invest a lot in marketing. This is one of the ones though that will come from produce of many countries. This is, yeah, it says it there. So this is going to be a altogether milder, um offering. It it's going to be quite bland in in my personal opinion. And and and I mean, the manufacturers would say who who are big, you know, big industries might well say, well, that's because people like bland oils. Um but the problem is that that that is a self-fulfilling prophecy. If you market and tell people this is how an oil should taste, there's some research in the states which showed that actually people have a preference for rancid oil.
Dr Rupy: What?
Dr Simon: Yes.
Dr Rupy: Oh my god.
Dr Simon: Because that's what they're used to. So there's a bit of education to do there. So um so I I think we we we we probably well, I mean, we we taste in blue glasses. And and theoretically, we we we should, I mean, we're not having a blind tasting. Um but you know, in in if we were tasting um for a competition or if we were tasting even if we were um we were Italian policemen, we we we would be blinded so we wouldn't know, you know, we wouldn't know where the oil came from. But we can see, so we'll have some indication because it's been shown it changes our perceptions automatically. Which is why they go in the blue glasses because we have a perception that um colour affects the quality, whereas in fact, actually the science shows that colour is indicates the amount of chlorophyll remaining in the oil, but actually it doesn't have any it doesn't have any impact. So you can have a really, really beautiful oil that's quite yellow in colour. Or you can have a very, very beautiful green um green uh oil that that that is also. But we tend to think of the yellow oils as being less high quality, partly because we can see the refined um oil over there looking looking very yellow. Um I I am I would need to have blue glasses because I am really seduced by um by green green oils. I love it. And it's visually it's just so beautiful. But totally. The the the science is that um that you know, you can get good oils that are that are that are green, you can get good oils that are um that are slightly more yellowy, um and and and vice versa.
Dr Rupy: Okay, great. I've just noticed something on the Filippo that I haven't noticed before. It says cold extracted on the bottom on the back. What is cold extracted versus cold or pressed or mechanically processed?
Dr Simon: Okay. So um means nothing. I thought you were going to say that. Yeah, yeah. So first cold pressed is something that you see um on on a lot of uh on a lot of a lot of oils. It's actually these days actually quite meaningless. So previously, in previous times, there used to be a first pressing to to get the finest and best oil out of the of the olives. Um then because you you had a donkey and a stone and your donkey was going around and the stone was. Then you'd have a mush which which you could actually get more oil from. So you'd go and have your lunch and a glass of wine and you'd come back and donkey goes round again and there's a second pressing. Um these days with our efficient mills, we just do the one pressing. Okay. Um and so anything that comes out, you hope is extra virgin olive oil and and it's not it's not chance, you know, you know it's going to be extra virgin olive oil, particularly early on in the season, particularly if you you know you've got a great harvest and you've looked after and maintained your your your olives really, really well, handled them well in their harvesting, brought them into the uh to the mill with minimal exposure to heat, light and and and oxygen. Um and then the second and then anything after that that doesn't pass the standards will go off to the refinery. So there's no second pressing. Cold, so you know, extra virgin olive oil is produced at temperatures under 25 or 26 degrees centigrade. That's not mandatory, but it's just that if you heat the oil, it will lose its polyphenols, it will lose its taste, it won't have those tasting notes and it will therefore not be extra virgin anymore. So so although there used to be great store set by by cold pressing, um I mean, you're certainly not heating, which you would do to get the extra, you know, to get the refined oil. So but but if you're treating it well, which includes keeping the system cool, then it either will or it won't come out as extra virgin. You hope it will. So it will have been cold pressed if it's extra virgin olive oil, at least it will have almost certainly been under 25, 26 degrees. So so those things don't mean anything. There is there is though some mandatory um um International Olive Council um um wording, which basically describes extra virgin olive oil as superior category olive oil obtained directly from olives and solely by mechanical means. So that is how the uh the IOC define the process of making extra virgin olive oil and then you add to that the chemistry and the taste test to make sure that it is.
Dr Rupy: Okay. Great.
