ZOE Science & Nutrition: Best of 2024 – Part 1

Let’s take a look back at our best episodes of 2024. We had an incredible lineup of guests this year who shared a huge range of actionable tips on improving your nutrition and gut health. 

A lot of what we learned might surprise you. Like the beverage you’re probably drinking every day that we thought was bad for us? Turns out it can actually be super beneficial.

Or that what counts as a plant is actually so much more than just fruit and veg. Not forgetting the topic we’ve shattered the taboo on, which made our celebrity guest emotional. 

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Transcript

Jonathan Wolf: Thanks for tuning in again to ZOE and to this very special episode, where we’re taking a look back over 2024. In fact, it’s a two-parter. There were just so many amazing insights from this year. 

A lot of what we learned this year surprised me, like the beverage you’re probably drinking every day that we thought was bad for us. Turns out it’s actually super beneficial. Or, that what counts as a plant is actually so much more than just fruit and veg. 

Not to mention the really important topic that until very recently was taboo, and made our celebrity guest emotional, I know I learned so much from that one. That’s coming up at the end of the episode so make sure you stick around. 

With January around the corner, a lot of us are thinking about making some positive changes but new habits can be really hard to stick to. I know my yearly resolution of giving up dark chocolate after dinner always falls by the wayside before Valentine’s Day. 

That’s why we took a deep dive into this very topic: how to build healthy eating habits in a meaningful, sustainable way. I chatted with the brilliant James Clear, author of the number-one New York Times bestseller Atomic Habits. We were also joined by Dr. Federica Amati, our head nutritionist here at ZOE.

James Clear: So it's mostly about how you structure your environment. And I think a simple question to hold in the back of your mind, just think about one habit that you're trying to build. Maybe it's a certain type of food you're hoping to eat more of, or, you know, something you're hoping to, maybe you just want to cook more meals or something like that. 

And then walk into the rooms where you spend most of your time each day, your kitchen, your living room, your bedroom. Look around those rooms and just ask yourself, what is this space designed to encourage? What behaviors are obvious here? What behaviors are easy here?

If you walk into one person's house and the chips and the cookies and snacks are on the counter and visible and easy to get to, and you walk into another person's house and those things are either tucked away. Maybe some of them already have been in the house or they're on the highest shelf in the back of the pantry and they're harder to get to, and they've got a piece of fruit out on the counter. 

Jonathan Wolf: That really struck me, that our environment is crucial in building new habits. Another key tip is to start out small, by asking yourself what you’d be most likely to stick to on a tough day. 

James Clear: One of the most common challenges with building new habits is that people bite off more than they can chew. They decide to try to do too much. And I have made this mistake more times than I can count so it is something that is very natural to do.

I think particularly for ambitious people, there's kind of this conversation in their head where they sit down and they start thinking about the changes they're going to make. And then the assumption in the back of their mind, even if they don't state it explicitly is, man, what could I do if I really got going? What would peak performance look like for me? If I was like really on my game and living my best days, if I really had my habits dialed in, what could I achieve? 

And I think when you're in that mindset, which is great, it's great to be hopeful and dream about where you could go, it's also really easy to end up doing too much. Oh, well, I'm going to change five, six, seven habits at the same time. And rather than asking yourself, what could I do on my best day, I actually think the place to start is by asking what can I stick to even on the bad days. That becomes your baseline and that becomes the new habit that you try to get established.

Once you establish that, then you can start to feel successful and feel like you're moving forward. You gain some progress and a feeling of momentum. And then, great, now you're showing up each day and there's all kinds of things that you can do from there. 

Jonathan Wolf: And so does that mean your guidance is in general don't try and make this massive change all at once, but think about this more as a series of smaller habit changes step by step. And is that in fact, what the sort of the science shows is more successful? 

James Clear: So let me give you two examples that'll probably help clarify. So the first one, this is just a really simple tactic. I think a very actionable thing that you can use for building better habits. 

I call it the 2-minute rule and it just says, take whatever habit you're trying to build and you scale it down to something that takes two minutes or less to do. So reading 30 books a year becomes reading one page. Or do yoga 4 days a week becomes take out my yoga mat. 

Jonathan Wolf: One thing I was left wondering, along with many of our listeners, is how long does it actually take to form a solid new habit.

James Clear: So this is a very common question. How many days does it take to become a habit and so on? You'll hear 21 days, 28 days, 30 days, 90 days. I don't know. There's all kinds of stuff that people say, the answer is it depends. 

There was a study that shows that on average, it takes about 66 days to build a habit. So that's a common number you'll see floating around now. Science says it takes 66 days. But if you actually read the study, the range is quite wide.

So something pretty easy, like drinking a glass of water, might only take a couple of weeks. Something more difficult, like going for a run after work every day, might take 7 or 8 or 9 months. 

Even that, I don't think, tells the story very cleanly because you can imagine one person who wants to build the habit of going for a run after work who lives with people who nobody is working out, and nobody's interested in that and it kind of goes against the friction of that group. And then another person who lives with all athletes that are excited about working out and they just need to join their friends to do it. Obviously, these are two different circumstances and so it's going to depend. 

But I think the real answer, the honest answer, to how long does it take to build a habit, is forever. Because if you stop doing it, it's no longer a habit. And what I'm trying to get people to realize with that answer, is that we often think about our habits as this finish line to be crossed, but they're not a finish line to be crossed. It's a lifestyle to be lived. 

Jonathan Wolf: For many of us who are parents, we’re also thinking about how to help our kids build healthy habits. James had some tips there too.

James Clear: The first thing is to model the behavior that you want to see. To ask somebody else to do something and then to not do it yourself, your kids are almost always going to imitate your behavior more than they listen to your words. And so if you want them to act a certain way, then you should try to set the standard as well. 

People often play to the standard that you set, not the one that you request. And so how can you showcase that? 

Another example is related to healthy eating and perhaps to kids. Let's say you want to get your kids to eat more greens or eat more salads. I just talked to a woman who wanted to get in the habit of making a salad for lunch every day. And when she started, at first she had this idea in her mind that it had to be pure and perfect. That it wasn't, if it wasn't like a perfectly healthy salad, then it wasn't worth it for her to do it. 

Then she shifted to this idea of what would it be like if it was fun. And so she tried to make each salad bowl like a party and she would put little toppings on it. And she even, someday she would even crumble up potato chips and put them on or whatever, but it made the habit enjoyable. And then, once she got to the point where she was actually having a salad 90% of the days, there are all kinds of ways to improve that and to optimize it, because she's actually showing up and eating it every day. 

So I think you can take a similar sort of approach, whether it's with yourself or with your kids and whether it's an eating habit or something else. What would it look like if this was fun? Let's start there, get the habit established, and then we can optimize and improve it from there.

Jonathan Wolf: What would it look like if this was fun? For me that seemed such a light, encouraging place to end our chat with James and definitely makes my new resolution for 2025, which again is to try and cut down on that dark chocolate after dinner, seem much more attainable.  

Find the full episode here: The science of eating well: How to master healthy eating habits Spotify | Apple

Jonathan Wolf: If you’re also thinking about a change you might want to make in 2025, let’s take a look back at one of the year’s most popular episodes for some inspiration. Legendary chef Hugh Fearnley-Whittingstall and my ZOE co-founder Professor Tim Spector are encouraging everyone to eat more plants. More specifically, to eat 30 plants a week. 

It’s believed that eating 30 plants a week could lower cancer risk, and help you live more healthy years. To me, it sounded like a lot of plants and potentially really expensive. But our guests for this episode helped me understand it could be neither.

Hugh’s first, key point was that plants are not just fruits and vegetables.

Hugh Fearnley-Whittingstall: Absolutely, that's right. Fruit and vegetables being a fantastically important and indeed delicious and useful group of plants, but there's much more to it than that.

One of the things I've really enjoyed doing in the book, is exploring the store cupboard and reminding people that there's lots of really great plant ingredients, whole plant ingredients, you know not processed but that comes from the store cupboard.

So I'm thinking of nuts, seeds, spices, pulses, these kind of things. They all count at least Tim assures me that they all count and this is what has been the basis of my most recent exploration of what I think is a really excellent way of eating 

Jonathan Wolf: Encouragingly, pretty much all the plants that we consume have some benefit on health. That’s firstly because they contain a lot of fiber.

Professor Tim Spector: And we know that total fiber is very important. The magic figure is for every five grams of fiber, you're going to reduce your overall risk of mortality by about 14%.

Jonathan Wolf: When you say reduce your chance of mortality for regular people listening, that's just reduce your chance of dying by 14%. 

Professor Tim Spector: Correct, yes. So you reduce your risk of dying by around a sixth, just by five grams of fiber. And just to put it into context, the average U.S. person has about 15 grams of fiber. So just increasing with 15 grams to 20 grams will give you this improvement in your lifespan. 

Jonathan Wolf: But also because plants contain polyphenols, which interact with our body and specifically our immune system, helping to regular our brains, behavior and more. Tim and Hugh had some tips on choosing plants based on their polyphenol content.

Jonathan Wolf: And Tim, can I just clarify, so you're saying if you're looking at a vegetable, like in a store, this is the way you figure out whether a vegetable has more polyphenols? 

Professor Tim Spector: Yes. So I didn't know any of this before I started researching my book 10 years ago. So I don't expect most people to know it, it's not really taught. 

It's the shape, the color, and then the taste if you can nibble a bit in the greengrocers, which you may not be able to. They're all clues as to the polyphenol count. So the more bitter and strong, if the leaves are loose, interestingly, that means they've had less protection structurally, so they have to be tougher and have more chemicals in them. 

Hugh Fearnley-Whittingstall: If we can avoid it, we shouldn't discard the outer leaves of the lettuce and the cabbage. They often have very tender white middles, which are effectively blanched. 

I always think of that in terms of they've been prevented from photosynthesizing in the heart of the plant, which is often why the middle of the plant is sweeter and why traditionally you actually tie up celery and endives and things like that because you want that white, slightly sweeter heart from a flavor point of view. 

But from a different flavor point of view and health point of view, those greener, more open, outer leaves have probably got more going on in them in terms of polyphenols, just as they’ve probably got more bitter flavors. Which now we might try and cultivate that taste because we know it's good for us. Therefore, let's enjoy the bitterness of those plants and sort of find a way to relish it. 

I mean, from a chef's point of view, we traditionally have, and a lot of us still do, including myself from time to time, we get very, very excited about animal protein, about meat and fish, and we make a massive fuss of it. We obsess over how we're going to marinate it or get the skin crispy or get the crackling. 

Once you've obsessed over those ingredients, you haven't got a lot of time left to think about the plant or the veg, which does then become the bit on the side. So we have to recognize that they're slightly tyrannical ingredients, meat and fish.

I'm still an omnivore, I enjoy them both, but we've got to just put them on one side from time to time and then focus on making plants delicious, which turns out not to be hard at all. 

Not least because from the plant kingdom, you've got the greatest variety of textures, flavors, and aromas far greater than you could ever get from the world of animal protein.

I mean, a pork chop is different from a chicken drumstick, but it's not nearly as different as a walnut and a peach, or a leek and a strawberry. These plants are really different from each other. And from the point of view of flavor and just being excited in the kitchen, we've got to remind ourselves of that often.

And that's why a great variety of plant ingredients coming into the kitchen is exciting. We shouldn't see it as just what we all should be doing now for our health. It's what we ought to want to do because it brings so much flavor and excitement into the kitchen and onto our plates.

Jonathan Wolf: So not only are plants vital for our health, but with a little imagination they can be the main attraction on our plate. But where does this number 30 come from?

Professor Tim Spector: We showed that the people with the healthiest gut microbes, which we defined by diversity, different types of species, were eating the most variety of plants. And this came out at around 30. 

So we saw big changes in the good gut microbes that have been associated with good cardiometabolic health and reductions in those microbes that have been shown to be related to poor health and poor diets.

We also showed improvements in mood, energy, and a reduction in hunger and a number of other parameters. So it was really exciting to see how we sort of take this epidemiological concept, which is just based on observational data, and then do a randomized control trial that had such convincing results.

Jonathan Wolf: For anyone who thinks it sounds challenging to eat 30 plants a week,  like I did initially, it’s less difficult than you might think. 

Hugh Fearnley-Whittingstall: Don't worry that we're sending you off to buy lots of expensive obscure plant ingredients that you haven't heard of, don't know what to do with, and might not like.

The first thing is to remind yourself that there are many, many, dozens, maybe over a hundred plants that actually you already like. You're going, really? Yes, there really, really are. 

And that's why I've done a big plant list in my book. There are over 200 plants on the list. I did put a couple of seaweeds there because I think it's a really interesting ingredient, but every other plant on that list, you've heard of it, I promise you, you've heard of it. 

You've heard of the spices and the herbs and all the main vegetables. You've heard of the pulses, the nuts, and the seeds. With a lot of them, you might not have put them in your cooking for quite a while, just because of the habit you're in. 

The first thing is to remind yourself there are lots of plants out there that you already like. Some of them might be in your kitchen cupboard already. 

Being able to put together plants-only meals, I think is really important for omnivores as well as people who choose a vegan or vegetarian approach. We do not need meat and fish on our plates every single day. 

Jonathan Wolf: And Hugh, is that almost your first tip? To say it's okay to have a dinner that doesn't have any meat in it? And that suddenly opens things up. 

Hugh Fearnley-Whittingstall: Yeah, not just okay, but important to do that pretty regularly and to feel comfortable with ingredients in your kitchen. That you can make delicious meals that your family is going to enjoy without putting meat and fish in them all the time. 

And I think that there's a whole bunch of ingredients that are really useful for doing that. I always have lots of tins of different pulses in my store cupboard, not baked beans in tomato sauce, but different types of white bean, black bean, chickpeas, lentils.

I have dried versions as well, particularly lentils because they cook so quickly. But you want things to be easy, and cracking open a tin of beans and adding them to a big stew with lots of other lovely flavors, tomatoes, chilies, spices, and herbs, add a depth of flavor to a lot of these dishes that make them really very, very enjoyable.

Jonathan Wolf: Hugh left us with some quick, easy ways to pack more plants into your meals, like a homemade trail mix with nuts and seeds, a delicious butterbean hummus, and garlic butter on greens. Especially handy for picky young eaters. Do make sure you go back and listen to the full episode to get all of those great cooking tips.

Find the full episode here: How to eat 30 plants this week, with Hugh Fearnley-Whittingstall Spotify | Apple

Jonathan Wolf: One of our most fascinating episodes this year was about dementia. It’s something I know has affected so many families out there including my own. And I really wanted to hear how we can put emerging science into action on this. So I spoke to dementia expert Claire Steves. She’s a medical doctor, a professor of aging and health, and head of the Department of Twin Research and Genetic Epidemiology at King's College London. 

Claire Steves: So dementia is actually an umbrella term. So lots of different things actually fit into that term of dementia.

But if we want to sort of classify it, it's a condition that involves cognitive function, so thinking and learning and memory. More than one domain of it, which is altered in somebody. That that's altered to such a degree that it then causes a problem in day to day living and that it's gradually progressive over time and needs to have been around for longer than a six-month period at the very least.

And actually, most people who get diagnosed with dementia have probably had some symptoms going back for maybe years.

Jonathan Wolf: For me, the million dollar question was can our lifestyle or even diet have any impact on our risk of getting dementia?

Let's start with me. So, I'm someone in my late 40s, I really want to make sure that I don't have dementia. Give me the advice. If I was walking into your clinic, tell me what you would be saying that I should be doing in order to try and make sure I never had to come back to your clinic in 20 years.

Claire Steves: So actually what I realistically say to patients is, it's about getting as many different colors of fruit and vegetables into your diet as possible and making sure that you're getting good plant-based fats into the diet.

Because the brain is hugely metabolically active, it needs a lot of nutrients and we know that a wide variety of plant-based nutrients is really important for brain health. And I talk about colors because actually there's evidence that flavonoids are really key phytonutrients for brain development.

It may be because you're changing the microbiome because there's such a thing as a gut-brain axis. There are quite a number of studies now showing Mediterranean diet, it helps to improve cognitive health.

Jonathan Wolf: So there is real evidence? Doctors always say you should eat more healthily. There are real scientific studies that show that switching to this Mediterranean diet, which is high in the things you're describing and low in the more traditional Western diet of meats and like white bread and all the rest of it, actually has an effect on dementia.

Claire Steves: Yeah. And so you just mentioned the other thing, which is meats and white bread. So we know that there's a relationship between vascular health and brain health. 

Jonathan Wolf: And vascular health means?

 Claire Steves: The blood vessels within your body and your heart. That's because one of the other types of dementia that we haven't really talked about is a vascular dementia. And often there's a combination, actually, of vascular factors that then bring on those other processes like Alzheimer's. 

Jonathan Wolf: So if you're eating a diet that's good for your heart, basically, that’s also going to be good for your brain.

Claire Steves: Yeah, it's going to be good for your brain and it's going to put backwards the balance of things that are going on in your brain that might relate to Alzheimer's. 

Jonathan Wolf: So if you can change your diet in a sustainable way, it really can reduce your risk of dementia. What we also learned in this episode is that exercise is key. 

Claire Steves: So probably the most evidence is around resistance training exercise for overall frailty and so on. Then for cardiovascular fitness, there's aerobic exercise. 

Jonathan Wolf: I'm one of your patients, I'm not very physically active. What would you be telling me that I should do that can really make a difference?

Claire Steves: Walking. 

Jonathan Wolf: Walking. 

Claire Steves: I think you need to get out and do walking 45 minutes, at least three times a week. 

Jonathan Wolf: And that would really make a difference. If I'm not doing that, that would really make a difference. So that, I think again, is amazing.

Claire, I think you were like, well, it seems sort of obvious. But again, I think many people listening to this grew up with the assumption there is nothing you can do about it, it's just literally a consequence of getting older. And you're saying actually, if you went reward three times a week compared to just not doing that, you're going to make a really significant reduction in risk is rather extraordinary.

Find the full episode here: Dementia: Prevention, genetics, new treatments Spotify | Apple

Jonathan Wolf: For me, one of our more intriguing episodes this year was about coffee. Something you probably have at least one cup of every day, and contains the world’s most popular psychoactive drug, caffeine. But could coffee actually be healthy? 

I chatted with renowned coffee expert James Hoffman, who’s the best-selling author of How to Make the Best Coffee at Home along with our very own Tim Spector.

Professor Tim Spector: For many years, we thought coffee was bad for us because short term, it increases your heart rate, increases your blood pressure. For decades, people said this is a rather dangerous thing to be having, don't do too much of it, you're going to have a heart attack. 


Then they started doing some proper studies and it was shown that based on over 25 studies, you can now see a reduction of about 25% in your risk of a heart attack or heart disease.

So then you're saying, why would that be something that short-term might be slightly stressing your system is actually long-term good for you? 


I think it's seeing coffee as this fermented plant that has microbes acting on it, has hundreds, thousands of chemicals produced from it, and it's probably a combination of all those things that gives it this health benefit, such as the fiber in it. We used to not think of coffee as a fiber-rich drink, but we now know that broadly you can get about 1.5 grams of fiber out of a cup, which means if you're having three cups a day, that's 4.5 to 5 grams of fiber, which is a quarter of your daily fiber intake in the U.K. and the U.S. 

 Jonathan Wolf: I always find it extraordinary because I always somehow in my mind, think about fiber as being this roughage-like bran. Or the stuff that my grandmother might stir into a glass of water.  


Professor Tim Spector: Yeah. And two cups of coffee is more than a banana in terms of fiber.  


Jonathan Wolf: So this drink that has been demonized as harmful could actually be quite beneficial. Tim explained some exciting new research to do with a mysterious-sounding microbe.

Professor Tim Spector: Exactly. It's like a forensic test, you know. Rather than doing questionnaires, you just take a bit of that stool sample, extract the DNA and you find this microbe called Lawsonibacter named after Dr. Lawson. And it's inevitably linked to the consumption of coffee. And then we found that it then produces these chemicals that through the fermentation process turn out to be really healthy for us and have been shown to reduce blood pressure and reduce blood sugar and things. 

Jonathan Wolf: Tim and James left us with a couple of tips to guide our coffee consumption; firstly give the instant coffee a miss, as it’s pretty low in these helpful polyphenols. And secondly, do go for decaf if you want to skip the buzz, as you’ll still get most of the health benefits. 

Find the full episode here: Coffee's hidden health benefits Spotify | Apple

Jonathan Wolf: Another wonder food product we delved into this year was olive oil. Incredibly, it regulates blood sugar, helps with weight management, and prevents long-term disease. For this episode, Tim and I met with olive oil expert Elizabeth Berger. She’s the founder of Frantoi, which works with growers and millers across Italy to harvest exceptional extra virgin olive oils. 

Professor Tim Spector: There hadn't been any large-scale, long-term studies until 2018 when they did something called the PREDIMED study. It was randomized, but not blinded, because they were delivering large amounts of olive oil to 7,000 Spaniards, large amounts of mixed nuts to another group, another group that were just given the standard Mediterranean meals. 

They followed them up for six years and this was the best study that had been done and clearly showed that the olive oil group had these really significant reductions in heart disease, strokes, and breast cancer.

Jonathan Wolf: So Tim, I just want to be clear, the drug intervention in this study over six years was literally they just got sent bottles of olive oil and the people who got sent bottles of olive oil actually had lower levels of strokes and things like this.  

Professor Tim Spector: And heart disease. 

Jonathan Wolf: It sounds crazy, right?

Professor Tim Spector: Yes, and breast cancer and some signs that are getting less brain dysfunction leading to dementia.

So it was an amazing study because it was a huge logistic exercise to keep people stocked up with this. And they were giving them the equivalent of about four to five tablespoons a day. Which actually is not far off some levels you'd have in bits of Greece, for example, which would be seen as quite normal, but a hundred times more than you get in the U.K. or the U.S. where we're only really drinking one bottle of olive oil a year, as opposed to one every two days in many Mediterranean countries.

So this, I think, was a fairly pivotal study, But there've been other ones since in the U.S. showing that it's not just a Spanish thing because they were sponsored by the olive oil industry, and Spain does have a slight interest in promoting it. They're the biggest producer in the world. 

But in the U.S., the cohort studies comparing olive oil drinkers against non olive oil have found virtually the same results. So I think we're now very confident that drinking extra amounts of olive oil, and particularly extra virgin olive oil has these major benefits. 

But it's not just the fats. So the epidemiology study, which has measured things like fat levels changing suggests that it's actually the polyphenols. We've mentioned these before on a number of podcasts, these defense chemicals in the plant and this time in the olive fruit that are conveying the benefits to the body. Because they are the key antioxidants. 

They are the ones that nourish our gut microbes, and they're in huge numbers in olive oil compared to other foods. You can sort of see how, if anyone's had olives or olive oil, there's some similarity, and it's because of those defense chemicals in your mouth that are, as well as defending the plant, end up nourishing our gut microbes and perhaps helping our immune systems to then fight disease and aging and all the stresses of life in the cells.

Jonathan Wolf: And is the level of polyphenols in olive oil very high compared both to other oils, but I guess also to other plants that I might eat? 

Elizabeth Berger: There are 36 known polyphenols in extra virgin olive oil, and I guess if you would compare that to coconut oil, for example, there are six. So it's a much more complex mix of polyphenols in extra virgin olive oil.

And for example, one of those polyphenols is oleocanthal. It's the polyphenol that gives a slight burn in your throat when you're tasting really, really decisive extra virgin olive oil, so peppery olive oil. 

Oleocanthal exists naturally in olives. It's one of the components in ibuprofen, for example. So it shows us that it's an incredible natural anti-inflammatory. 

Professor Tim Spector: Extra virgin olive oil is probably one of the best sources of polyphenols you can get. Certainly in any oil that we drink normally. But it's also related to the quality. 

So the higher the quality, the greater the concentration and diversity of polyphenols in it, which I think is a really important message. And the lower your quality, it gets diluted, and you don't get nearly the same benefit. 

Jonathan Wolf: But a really important point here is that how you buy, store, and cook with olive oil really matters in order to get these benefits. 

Elizabeth Berger: So the process is that the olive oil is produced and then it typically naturally decants. So it takes a little bit of time where the sediment falls to the bottom. You then have a choice as a producer, whether you filter or you don't filter in terms of, super high quality, you would wish for a light filtration of your oil.

And there's a reason for that because an unfiltered oil and I'm sure that this is one of those myths that's out there, that an unfiltered olive oil is really great because you see it in those lovely clear bottles and it's got that lovely cloudiness. It must be the real deal. 

It's actually not. That's actually not great for a couple of reasons. One, you shouldn't have your olive oil in clear glass because it will change its quality. So you're looking for dark glass as the very, very best format for extra virgin olive oil. But the other thing is that that sediment that is in suspension in the olive oil will actually start to oxidize the oil with time. 

So anything that needs to be shipped, we have to think about these things. If something's being shipped globally, it does need to be stable. And so a light filtration won't change the quality at all. It will actually enhance the quality because it will give it a little bit of stability in terms of shipping.

Jonathan Wolf: So to confirm, if you see a bottle of olive oil that says it's unfiltered and has some sediment in, which I've definitely seen and always thought that looks pretty cool and very authentic. Actually, that's a complete no-no, don't buy that because basically that sediment will have been continuing to react with the olive oil and I'm going to lose the health properties we're talking about. 

Elizabeth Berger: Exactly right. 

Jonathan Wolf: Keep your olive oil somewhere where the temperature is steady, like a cupboard. A key question that a lot of people have is can you cook with olive oil? Or will that affect its health benefits?

Professor Tim Spector: So if you're starting with a good quality olive oil, you're still going to end with something that is stable, not causing problems, it's still got plenty of polyphenols. But if you cook with it, you're not getting the same benefits as you would if you're having it on a salad or you're having it spread over your fish once you've cooked it.

Elizabeth Berger: Exactly. And so therefore, if you've got a very high-quality olive oil, you may prefer to keep that as a raw ingredient rather than cooking with it. But the benefit as well, whilst the polyphenols might be dropping down when you heat them in the olive oil, they will improve the nutritional content of the ingredients that you're cooking.

So let's say, for example, that you roasted some carrots with extra virgin olive oil. It will improve the nutritional content of the carrot, not just decrease the level of polyphenols from the olive oil. So there is an upside. So there's no question that you should be using it to cook with.

Jonathan Wolf: I'm coming away just even more reinforced with this idea that olive oil is really great for my health. And I should be trying to have more of it. Could both of you maybe share a tip on an unexpected way to incorporate olive oil so that we can get more of it each day?

Elizabeth Berger: I would replace butter at every step of the way with extra virgin olive oil. Because I think it's an extremely good thing to do for your health, but also for the flavor. 

I would start with breakfast. So on your toast, if you like marmalade on toast, try to put a little bit of olive oil underneath your marmalade. It's wonderful. It's uplifting, you know, it makes you feel brighter in the morning.

If you make granola, make it with olive oil. And if you favor sweet things at breakfast time and you perhaps I don't know, make a cake of some sorts, certainly as they do in Italy and the Mediterranean, then make it with olive oil because it will make a moister cake. It'll hold for a few more days and you're just upping the level of olive oil in your diet.

Professor Tim Spector: Agreeing with most of those, certainly really, I hardly use butter at all. I just reach for the olive oil every, every time. 

Find the full episode here: Olive oil: how to unlock health benefits Spotify | Apple

Jonathan Wolf: And finally for part one in our whistle-stop tour of 2024 ZOE episodes, I took a step back and we had someone very special take over the microphone.

Davina McCall: This is Davina McCall and I'm in the driving seat today and I'm going to tell you why. 

You see, there's a stage of life that every single woman goes through and it's not spoken about much. Your mum probably didn't tell you about it, your teacher never taught a class on it, that's for sure. But let me tell you something, if you've not been through this stage of your life already, it's coming for you. So I suggest you prepare yourself.

For way too long we've kept quiet about the menopause, the onset, the symptoms, the treatments, but those days are over. Today, we are shouting from the rooftops. 

So back in 2022, I published my book, Menopausing. What I really wanted to do was change the way that society perceived and saw us as midlife women and I wanted to share what I learned with you. 

I'm joined by my friend, Dr. Sarah Berry. She's a professor at King's College London and chief scientist at ZOE. And she's just led a new study about how diet affects menopause symptoms.

And Jonathan's here as well. There's two really important reasons that Jonathan's here, obviously, he asks really good questions, but also because we need men on side. We really, really need all the allies we can get to hear us, help us, support us.

Jonathan Wolf: All right. Did you think you were going crazy when you were first in perimenopause?

Davina McCall: Yes. 

Jonathan Wolf: When you first started having perimenopause or symptoms, did you realize what they were? 

Davina McCall: No. 

Jonathan Wolf: Okay, we're going to come back to that. Sarah, can you suffer severe symptoms from menopause without hot flashes or disturbed sleep? 

Prof. Sarah Berry: Yes. 

Jonathan Wolf: Does menopause increase your risk of many chronic diseases? 

Prof. Sarah Berry: Yes. 

Jonathan Wolf: Can the right diet significantly reduce menopause symptoms?

Prof. Sarah Berry: Yes. 

Jonathan Wolf: And Davina, you get a whole sentence for this. 

Prof. Sarah Berry: You're lucky I didn't get the sentence. 

Jonathan Wolf: What's the biggest myth that you hear about menopause? 

Davina McCall: Women lose significance, importance, you become invisible, they are dried up, and life is over after menopause. And it's not. 

Jonathan Wolf: Davina went on to share her own personal journey through menopause and HRT and I really urge you to go back and listen to that episode in full because it’s truly incredible. Then Davina and Sarah had a fascinating discussion about menopause symptoms.

Prof. Sarah Berry: What's really important is to remember there's more than about 50 symptoms, and it varies from one individual to the other. It varies the time course of symptoms, the duration of the symptoms, the intensity of the symptoms. 

That's because estrogen receptors are all over our body. It's estrogen that declines mainly in the menopause. So that's the primary reason we start to have all of these experiences. We have estrogen receptors throughout the body that affect things like our hunger, our energy, our mood, as well as our heart health, our muscles, our bones, et cetera. 

So once you have this decline in estrogen, which is what happens in menopause, that's why you can have so many varied types of symptoms. 

I think what's interesting is what you described, Davina, is this fluctuation of symptoms. And this is really interesting as well because I think a lot of people think, okay, you hit 51, which is the average age of menopause, suddenly you've gone from premenopause or you're postmenopausal, that's it. 

But there's this whole phase before, which we call perimenopause, which is where your estrogen levels, as well as some other hormones, start to change. But you don't just have this beautiful, gradual decline in estrogen so that your body slowly just learns to handle it. It's like this crazy rollercoaster.

Jonathan Wolf: And Sarah, just to make sure I've understood that right, because I think I was definitely brought up with this idea that basically you hit menopause, everything is completely normal until then you stop having periods and it's all over.

But you're describing this long perimenopause period where you're saying almost from day to day the level of this estrogen is all over the place and that that is therefore what explains the description that Davina's talking about, about suddenly having the night sweats and then just switching off three days later.

Prof. Sarah Berry: Yeah, absolutely. So menopause is the point at which it is a year after your last menstruation, so your last period. 

But leading up to that, you have these fluctuations, these peaks and troughs in estrogen. It can last from two years to five years on average, but for some people, it can last up to 10 years. And it's that phase that's particularly troublesome in terms of all of these symptoms. 

Davina McCall: Can I ask you something? So lots of women talk about taking blood tests to see if they're perimenopausal or not, but that doesn't work, does it? Because if your estrogen is going up and down and up and down in a day, you're not going to know. 

Prof. Sarah Berry: Absolutely. And I think this is a huge waste of money, a huge waste of resources. And again, it's one of those myths that's so frustrating when people say, Oh, I've had my hormones checked and they're fine. It's like, okay, they were fine at that point in time but what about tonight, what about tomorrow? 

So as well as feeling rubbish with all of the symptoms, also it actually impacts your health. It impacts your risk of many chronic diseases, such as your chances of getting type two diabetes, cardiovascular disease risk, et cetera. And that again goes back to the function of estrogen. 

As I said earlier, estrogen impacts nearly every cell in our body. And so it impacts all of the different kinds of mechanisms and processes involved in the development of different diseases. 

Jonathan Wolf: Menopause had been this taboo topic, and it was also really underfunded in terms of the research. So Sarah shared some of her brilliant research into menopause symptoms that she’s been working on here at ZOE.

Prof. Sarah Berry: And what really shocked me actually, Jonathan, is that 99.8% of our peri and postmenopausal women reported having one symptom or more.

Davina McCall: That's not what I thought that you were going to say. I thought you'd have more people not having any symptoms. 

Prof. Sarah Berry: No. Obviously what symptoms they have are hugely variable. 

So we asked them questions about 20 different symptoms and we asked them about for each of these symptoms how severe were they on a scale of one to five. What we found was that 66% of this group had 12 or more symptoms. And again, that really, really surprised me. 

And what I found interesting is, because this is the first time we also looked at the severity of the symptoms, the symptoms that were most common, which was sleep and irritability weren't actually the symptoms that people reported as being most severe.

So we often think about irritability or sleep as being the ones that have the biggest burden, but actually, it was the other factors that caused actually the most burden to their life or really impacted them.

And this was weight gain, this was a change in their metabolism. Loss of libido, going back to your point, was something that although it was less prevalent, so less people had that as a symptom, it was what they said was the most impactful.

And then fatigue, people saying that's just one of the biggest problems having the kind of fatigue symptoms that have the impact that every day.

Jonathan Wolf: What we also learned in this episode is that hormone replacement therapy is safe and beneficial for most people. But it doesn’t always completely get rid of symptoms, so a holistic approach can be helpful. 

Jonathan Wolf: I'd really like to talk about diet and other lifestyle changes and whether these can impact symptoms, whether or not you're on hormone therapy.

I have to say that five years ago, so we were already into ZOE, I would have thought that reducing menopause symptoms with diet and what we're doing at ZOE would have an impact on menopause.

It sounded crazy, but Sarah, this is an area that's been a really big focus and interest of you. So we've ended up doing all of this study and you've just released this big new study. Can you tell us what you found and maybe explain what it is? 

Prof. Sarah Berry: Yeah, well, I would start by saying I would have agreed with you. Based on what little evidence there is about diet and menopause, that, oh, diet can't do anything, particularly because of all these crazy claims out there about supplements, about those silver bullets, whatever, that it will cure all of this. 

But we looked at this, we put it to the test in our ZOE Predict cohort, and so we followed 5,000 women over a period of up to about 20 weeks. And these were perimenopausal women who had signed up to take part in the ZOE membership program. So these are women who we did various tests to look at their metabolic health, their microbiome, and then deliver personalized advice to them based on some of these tests, but also based on their health history, where they are now with their diet, their lifestyle, et cetera.

We asked them loads of questions about their health at baseline and their symptoms and then we followed them up over this period of between about 18 to and beyond 20 weeks. Then we asked them at the end about their symptoms, about how many symptoms they had about the severity of the symptoms.

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What we found was around a 34% reduction in overall menopause symptom burdens. This is taking into account the number of symptoms and also the severity of the symptoms by following a healthier diet. And actually, when we looked into the details of the dietary changes, we weren't actually looking at seeing huge, huge changes in people's diet quality. 

I think that to me, Jonathan is what's most important. We are actually seeing relatively small and even just when people are having small shifts, we still saw a huge impact. And we saw across so many different symptoms. 

Davina McCall: I mean, talk about falling in love with you guys, like with all of my heart, because nobody helps us. Honestly, and when somebody does go, No, we see you, and we've got your back, and we're going to do some work on it.

It's so upsetting to think we're all going through this thing, and no one's helping. And this is something, it's not just medicine. This is something that literally, every single woman could do, and a 34% reduction. It's ridiculous. That's over a third. 

Prof. Sarah Berry: You know, I'm not a hugger, but I'm going to have to give you a hug now.

Davina McCall: But you know what I mean? 

Prof. Sarah Berry: Yeah, so I think as scientists, what we always want to do is look at our own results, but we want to look at them together with the bigger picture. Because there are other people doing research in this area. 

It's not only us, I'm very proud of what we're doing because we have the resources to do it at a scale that allows us to look at an individual level, what's going on. But there's many other studies that are also being run now, although it's slower than it should have been. 

Collectively what this research is showing is that following an overall healthier dietary pattern, a Mediterranean-style pattern, as we often call it, can reduce your symptoms. As well as it will help improve some of these risk factors that we talked about, associated disease, your blood lipids, your blood pressure, et cetera.

So the kind of fundamental principles here are reducing your heavily processed unhealthy foods, this ultra-processed style of food. So your very heavily processed red meats, for example, reducing refined carbohydrates, your pasta, your rice, your white bread.

But at ZOE we are always about what can you add in rather than what you have to take away. And so the great news is that where we see the biggest benefit is actually by what you're adding in. 

So adding in unprocessed plant-based foods. So fruits, vegetables, pulses, whole grains, oily fish, if you're not vegetarian. Having a decent amount of healthy oils, because we know that will help with many of these disease risk factors, but also, could help with the symptoms as part of this overall healthier diet.

Find the full episode here: Davina McCall: make this choice every day to reduce menopause symptoms Spotify | Apple

Jonathan Wolf: There you have it folks, some really actionable tips you can carry with you into the new year. From replacing butter with olive oil, to eating 30 plants a week. 

If someone in your life is trying to make healthy nutrition changes in their life, why not share this episode with them?