ZOE Science & Nutrition - How body fat impacts health and aging

Episode Date: November 30, 2023

As we age, the distribution of our body fat changes, particularly around menopause.   Most people think of body fat as bad, but fat tissue plays a number of hugely important roles in our health. In today’s episode of ZOE Science and Nutrition, Jonathan is joined by Dr. Sarah Berry and Prof. Deborah Clegg. Together, they debunk the myth that fat is bad, enlighten us about why body fat is distributed where it is, and explore the differences in fat distribution between men and women.  Deborah Clegg is a professor and Vice President for Research at the Texas Tech University Health Sciences Center, El Paso. Her research focuses on sex differences in metabolism, adipose tissue, and the brain and the impact this has on our health. Dr. Sarah Berry is one of the world's leading experts on human nutrition. She has run more than 20 randomized clinical trials looking at how humans respond to different fats. Head to zoe.com/podcast if you want to uncover the right foods for your body and get 10% off your ZOE membership. Download our FREE guide — Top 10 Tips to Live Healthier: https://zoe.com/freeguide Follow ZOE on Instagram Timecodes: 00:00 Intro 04:00 What is body fat? 06:32 What is healthy fat? 07:52 Female vs male body fat 11:56 Why is belly fat the most unhealthy? 19:43 Waist to hip ratio 21:24 How estrogen affects fat distribution 27:41 Perimenopause symptoms 31:01 Fat cells producing estrogen 36:00 Hunger the menopause 38:46 Weight gain and the menopause 40:54 Physical changes in men 42:28 Exercise and fat distribution  43:26 What to eat during menopause 46:37 Estrogen supplements Mentioned in today’s episode:  The evolutionary impact and influence of oestrogens on adipose tissue structure and function from Philosophical Transactions of the Royal Society B 2023 Menopause is associated with postprandial metabolism, metabolic health and lifestyle: The ZOE PREDICT study from EBioMedicine 2022  Episode transcripts are available here. Have feedback or a topic you'd like us to cover? Let us know here

Welcome to ZOE Science and Nutrition, where world-leading scientists explain how their research can improve your health. On today's show, we're delving into the science of body fat and its profound influence on our health. As we age, our body shape naturally changes. For many, this is most pronounced during menopause. But does our body fat really put our health at risk? And does this impact you differently if you are female or male? Here to replace myths with facts is Professor Debbie Clegg from the Texas Tech University Health Sciences Center, El Paso. Debbie's research focuses on the huge impact

that our hormonal and chromosomal differences have on our long-term risk of disease. Debbie, thank you so much for flying in all the way from Texas to join Sarah and myself today. Oh, I'm so pleased to be here. Thank you so much for the invitation. No, very exciting. Now, we always

have this tradition that we start with a quick fire round of questions, which professors find really hard because we have these strict rules that you can say yes or no, or if you absolutely have to, a one sentence answer. Are you willing to give it a go? Absolutely. Brilliant. All right. I'm going to start. Is it true that women naturally carry more body fat than men? Yes. Is body fat bad for my health? No.

Interesting. When I put on weight, is my body making new fat cells that I'm then stuck with? Yes. Right, over to me. So can carrying my body fat around the hips and thighs protect me from disease? Yes. Okay. Is it inevitable that my body shape will change when I go through menopause? Yes. And can body fat actually help keep me healthy as I age? Yes. Unexpected. All right, That's really interesting. Now you get,

you can actually answer with a sentence or two now. We're going to release the pressure. Last question. What's the biggest misconception around body fat and menopause that you hear frequently? Oh, the biggest misconception is that belly fat is bad. But as we transition through menopause, we start to accumulate it more in our belly. But that's where we're making estrogen. So I think we have to sort of embrace it as it's not bad. It just is. And I think maybe if we do that, life will be even better.

So I'm really looking forward to talking about this topic today. And I really enjoyed seeing you present a paper about a year ago, which is what triggered the idea of inviting you onto this podcast. I would like to start with a recognition that body fat is a very sensitive issue. And, you know, in our discussion today, I think we really want to focus on its role in health, not focusing on the numbers on the scale, which is obviously a very big part of the society in which we live. And we're generally bombarded with these messages that body fat is bad. In fact, that any level of body fat is bad, and that any level of weight gain is detrimental to our health. And I think what's interesting is your research suggests that this is more complex. And I think there's quite a lot of myths that we

can sort of bust today, which would be a lot of fun. I'd like to start right at the beginning. What is body fat? Oh, that's a great question, right? So as we eat, extra calories or even calories that we eat have to be stored somewhere. And so it's actually stored in a fat cell. We call it an adipocyte. It's a science-y term to talk about a fat cell. And that's where calories are stored.

So if you don't have enough body fat, it's actually as detrimental to your health as if you have too much. Because you don't have the energy that you might need. Exactly, right? It's absolutely critical. And women, it's even more critical. Our brain somehow registers how much fat we have. If we don't have enough fat, we won't be able to become pregnant. So it's really, really important to understand how incredibly wonderful body fat actually is. I think it's also something that, again, we think of it as being bad, but now we've discovered that it's like an endocrine organ. It actually secretes all of these wonderful hormones. It's really, really important for our health. And I'm quite surprised to hear that because I sort of think of fat as being this completely inert thing that we're carrying around. And I heard you say it's a store of energy. So I sort of understood that because it's a bit like, you know, when you're eating food, right? We know that fat and carbohydrate

are these sort of simple macronutrients. You're saying that it's not as simple as that? It's not. Because I think there are so many different ways in which fat is regulated that we don't often pay attention to. So it does store calories, but it also secretes hormones. And I think that the idea that all fat is bad is a misconception. There are fat cells that can be healthy, and women tend to have more of those healthy fat cells than men. So even when you were asking your questions, you were utilizing yourself as, you know, in me, I might

have responded differently if she were asking those exact same questions. So that's interesting. So what is healthy fat then? I think healthy fat is the type of fat, I love to call it spandex, right? So if you think of a fat cell, it's sort of basically a circle. And a healthy fat cell has the ability to expand when you have extra calories that you're taking in and need to be stored. An unhealthy fat cell is one that I think of as wool. It's a circle, but it's encased in connective tissue or fibers, and it has no ability to expand. And so all those extra

calories, instead of being stored in that fat cell, actually go into your liver or into your heart, go into places that are not supposed to be, and that's when it becomes very unhealthy. So what changes a healthy fat cell to an unhealthy fat cell and vice versa? Is it reversible? It's not necessarily reversible. It's a great question. But what a healthy fat cell is, is one that has this expandable capacity. And what makes it that way? Estrogen is one of the items that actually makes a healthy fat cell healthy. Men have estrogen as well. Oftentimes, we forget that men have estrogen. And so it's really the sort of the level of estrogens to testosterone that is so critical, but estrogens make this beautiful, expandable, spandex-y-like

fat cell. And so is body fat the same in males and females? No, it's very different, right? So, and I like to think back to why that might be. And I think it has to do with the fact that women, when we gain weight, and we have to gain weight in a really, really healthy fashion, our bodies are designed to do that. We store those extra calories in our hips and thighs in these beautiful spandex-y-like fat cells. Men, on the other hand, store their fat predominantly in their belly area. Their overall design back in the hunter-gatherer days was that the men predominantly were out there chasing the wild game. And so they had to store a little bit of fat so they would have energy to be able to chase, bring in the food. And so they would store a little bit of fat in their abdominal area because you could utilize that fat really, really quickly. And so that's where men store fat, where women put it in our hips and thighs, and it's bloody difficult to get rid of from our hips and thighs. But the women's fat is in this

really protective area. And then during breastfeeding, we mobilize the calories that are in those fat stores to support the calories that we expend for breastfeeding. And so, well, you're saying that as a woman, you're storing your fat in an area which you're describing spandex as like, it's quite easy to expand this and it's not interfering with any of the organs that are important for my health and that that might be related to things like breastfeeding where you're having to get a lot of calories. I've seen this, right? You get a lot of calories for your children, whereas men are storing this for whatever the biological underlying reason lot of calories for your children, whereas men are storing this for, you

know, whatever the biological underlying reason might or evolutionary reason might be, they're storing it around, like around their belly, tucked in with all sorts of organs, which I can think of the liver, but I'm sure you can tell me lots of others that are down there. And that is much more constrained. Yes, exactly. So those fat cells, you wouldn't want them to get too big, right? Because then all of a sudden, well, you see that now in aging men, you see big, big bellies, right? That's not what we wanted. We wanted to be able to mobilize a very small amount of extra calories that are stored in those fat cells for hunter-gathering days, right? And what's really fascinating to me is that if you have a male and a female, same age, they both go on the same diet, the man will lose weight

faster than the female. Again, because we are designed to gain weight and we hold on to those extra calories as much as we can. And so oftentimes I can talk to a man and a woman and they've gone on the diet together and the man will lose weight and all of a sudden he can cinch his belt up a little quicker, a little easier. It's like he's moved a notch on his belt where the woman is still struggling because she's still got those hips and thighs. And again, it's really, really difficult to mobilize that. But again, we have to embrace it because those are the really healthy fat cells, the ones that are in our hips and thighs.

And so, Debbie, you've said how the fat cells are different around your stomach versus your hips and thighs and how men might be able to lose the fat more quickly than females. What about within a female? Where can you lose it from more quickly? Is it more stubborn around the belly because of these differences? It is a little bit more stubborn, especially as we age. We'll go with someone who is premenopausal. And so what happens is that typically we love to store, again, the calories in our hips and thighs.

But once we've hit storage capacity such that the spandex has expanded as much as it possibly can, then we start to store it in other places. And that's when it starts to go to your belly. And so that's also when it starts to become less healthy. And then, again, that's in the premenopausal stage. I like to think of it as sort of their storage tanks. So you first fill up your storage tank, which is your hips and thighs. And then once those tanks are completely full, then it starts to shift in women into that belly area. And that's when we have a higher incidence of diseases such as diabetes, cardiovascular disease, even some cancers.

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go to zoe.com slash free guide or click the link in the show notes and do let me know what you think of it. Okay, back to the show. And do we understand why the fat is more unhealthy when it's sort of in the belly and around these organs? I think it's because when those fat cells, if they can't expand, and those fat cells are much more like wool, so we can use that analogy, then if the fat cells can't expand any further, then those extra lipid drops, those extra calories, then get stored into the liver, into the heart, into the pancreas. They get stored where they're not supposed to be stored. And also that when

those fat cells become full to capacity inside the abdominal area, they become inflamed. I think we've talked, you know, a lot of people talk about inflammation as being bad and inflammation within those fat cells inside that abdominal wall. That's when it's really, really bad and very, very unhealthy. Now, why those fat cells become inflamed, I think we're still trying to learn what that looks like. But it's fascinating if I were able to actually show you what they look like, right? Under a microscope, they look different when they're inside the belly versus when they're on their hips and thighs. So having that fat around the belly versus around the hips and thighs means that we're in this state of chronic, low-grade inflammation. It also increases

our insulin resistance, so it makes us less sensitive to insulin, so we have higher blood sugar peaks, for example, after we eat high-carbohydrate, rich meals as well. Perfect. Absolutely true, right? So those inflamed, unhealthy fat cells within that abdominal area definitely lead to insulin resistance. All of that extra inflammation leads to changes in a lot of different metabolic syndromes. So yes, absolutely. And it also increases our blood pressure. When people ask me, what's the biggest thing I can do to reduce blood pressure? Should it be that I go on a low-sodium diet? We always say, well, first, what's your waist circumference like? Can you lose a bit of the fat around your belly?

Why is it that fat around the belly particularly is linked with high blood pressure? I think it has to do with probably, again, the storage of those extra lipid droplets and that they're probably getting around. These are little droplets of fat. Yeah, exactly. They're inside the arteries. So getting rid of that extra little belly fat and reducing that level of inflammation will totally improve overall blood pressure. And I agree with you.

Blood pressure is one of those things we can't feel, right? You can't feel it when your blood pressure is elevated. And so people who are walking around, we thought it was all directly linked to sodium. But I think that we're finding out more that it may not be directly linked to sodium, but that there are other factors that really influence that blood pressure. Yeah, in the UK, in the US, the proportion of people are what we call prehypertensive. So haven't got a diagnosis of hypertension,

have borderline hypertension. Hypertension means high blood pressure. So they have borderline high blood pressure. That's the point in time where diet lifestyle and losing weight around the bed is really powerful to improve their health. But most people don't realize that they have high blood pressure or borderline high blood pressure.

Well, the other thing I realized that most people don't necessarily realize is like where their fat is being stored. So I have this personal experience because I've actually had a full body scan done in the past, a DEXA scan as it's called, which was when I was taking part in the first Zoe Predict studies. And this is actually a very depressing experience for me, Debbie, because I'm definitely not carrying lots of fat on my thighs or any of these good places. And it generally is like, well, I don't think I'm carrying very much fat at all. I had been putting on a bit of weight. This is like from the end of my 30s into my early 40s. I did this DEXA scan and it turned out that I was carrying quite a lot of weight all in what they call the visceral fat, right, which is this belly fat area you're talking about, nicely layered around, you know, my liver and my pancreas and various other organs. I don't really understand what they do. And this was a huge shock and also interesting, a bit of a shock to the nurse who was doing the scan as well, because I think, you know, she was surprised by how much was there. And so I guess that's a great example of what you're describing about as a man carrying your fat in

the worst possible place, but also suggests that it's not always obvious. It wasn't like I have like lots of visible body fat that would make you think that actually I had lots of fat in this really unhealthy place. Is that very unusual? And how can anyone listening to this figure out, you know, what is the reality of their fat distribution? No, I love that because I think that's the hidden secret, right? Which is that we don't often know where our body fat is distributed. We utilize in health and medicine, we utilize a body mass index, BMI, right? And it's this measurement of your height and your weight, but it doesn't tell you where you're depositing your fat. And so I often find

it to be a misnomer because if your BMI, your body mass index is elevated, oftentimes you say, oh, you're unhealthy, But you might not be. You might just be a person who has lots of fat in a really healthy place, and you might not be unhealthy. So I think it's – I love the fact that you went in and you actually found where your fat was. For you, I would say that's scary. That's a scary place to have your fat. And I would really actively get you to do more activity, more aerobic activity, redistribute that fat. But you might have a genetic predisposition to depositing more of your fat there.

I've improved my diet a lot since then. Don't worry him, please. I haven't. But it was definitely one of the things that really motivated me to take this seriously early on in time of Zoe, because it was a shock and it was very different from what I'd expected. Now, you just mentioned about one thing you could do, but just before we go there, if you just look in the mirror, how well does that tell you whether or not you are getting this fat distributed in your belly, which is what you're saying is what you should really be worrying about? Right. I think that the mirror can tell you a little bit

about it, but do that in the buff, right? You have to look at it. But again, I think it's important to love what you're seeing in the mirror, especially if it's still in those hips and thigh areas. I think that that's so incredibly important. So much of the time, we hate our fat when it's in our hips and thighs, and I just really want us to embrace that that's a very healthy place for it to be. I do wish that more of us had the ability to go in and get our body scanned so that we could find out exactly where our fat is located. I just had the same experience and I couldn't even believe that my muscle mass was so dramatically different between my right arm and my left, right? I mean, but I think those are so much more informative than just looking at the number or

just looking at a ratio of a number to another number. I would love more people to have that opportunity. I think that's brilliant. It's still quite expensive. I think we would love to be at a place where actually, you know, everyone who's Zoe could actually end up having that done because clearly it gives you this much more granular understanding, right, about what's going on and also see how potentially you might really be improving that with shifts you're making in your lifestyle, which are going to be less obvious externally. And as you said, if you're just looking at weight, for example, it may be really quite a poor measure as to what extent you're improving your health. The better way is the waist to hip ratio. I do love that, right? You have to make sure that

whoever's doing it, if it's yourself, that you're doing it from the same place, because it could be, you know, if you went an inch up or down when you're doing those measurements, you're all of a sudden, you might be devastated because it's changed. Lots of people will be listening and they'll never have heard of the waist to hip ratio. Could you just explain for a minute what that is? Why you think that's better than something like BMI? So we use waist to hip ratio actually for all of the research that we undertake looking at how diet impacts our health because we know it's a key metric of health for people that can't do complicated scans like you just did and we know it's better than BMI like Debbie said. What it does is it allows us to look at what the

relative distribution in quite a crude way of fat is around the waist. So what Debbie said is the unhealthy fat versus around the hips, which is the healthy fat. So get a tape measure, put it around where your belly button is, and then take the widest part of your hips, the widest part of your buttocks, and put a tape around there, and then work out the ratio. So divide one by the other. And so you're describing that often men will have a higher ratio, is that what you're saying, than women? Yeah.

So definitely the men will have a higher one around the belly button, and the women will have more of their fat in the hips and thighs when it goes around the hips. I think as well, Jonathan, particularly as a woman, we know when our bodies are changing. So I'm 46 now, Debbie. I'm starting that perimenopausal journey, and my body has changed. I know it's changed. I don't even need to look at myself naked in the mirror to know. My jeans are tighter. I, for the first time ever this year, I've got a little belly, so I might be slim. So my BMI is still in that really healthy range. But I know that I'm now laying down a fat tissue around the belly because of all the changes that happen due to menopause and estrogen. So I wonder if we could maybe dive into that a little

bit. Maybe could we just start very simple level? I think you mentioned this word already, you know, estrogen. Could you just explain just very simply, how does that affect what's going on? I know this is a big center of your personal research. It is. And I think that it's just fascinating. And so I want to let everyone, too, know, for example, even studying differences between men and women, this is relatively new, right? So in the United States, in 2016, the National Institutes of Health finally mandated that men and women were both studied. It used to just be that everything was done in men, whether it was a basic science study where you used rodents or whatever it happened to be, mice, rats, it was all done in men, males, until 2016 when all of a sudden they said, uh-oh, we're only looking at one half of the population. We don't even understand

the biology of the other half of the population. Which is completely shocking. I mean, this comes up quite often on the podcast, but every time I hear it, it's extraordinary. Yeah, I mean, it's what I've experienced. So before starting the Zolipidic research, I've run about 30 randomized clinical trials. Apart from one of them, they've all been in men. Now that's because it's very difficult to get funding. You can study half the number of people if you're just doing it in men. But actually looking back now, I feel bothered by the fact that I've only ever researched men. Fortunately, with the ZOE predictor research we're doing, we have access now to, you know, 60, 70% of our participants are female. So it's really exciting that we can probe

in so much detail now women's health. I think that as women, we have to be much more curious because we haven't been included in research. We need to now make sure that we are included in research. But even with that, women are so different. I know that I sort of got off track a little bit because we were talking about estrogens. But the reason I did that was because over our lifespan, our estrogen levels are changing. And so whenever we even compare what happens metabolically between a man and a woman, we need to make sure that we look at where she is in her estrogen cycle. I've heard it described, I think someone else telling me that just women's bodies are far more dynamic than men because I have all these hormones, but they're both changing a lot just on a maybe roughly four-weekly cycle. And then there's this big change sort of, you know, from puberty to menopause and afterwards.

So that men are like this very sort of simple and quite static sort of… You're not simple, Jonathan. I am a bit simple in that sense, right? In comparison to women, this is one of the reasons that people explain to me that a lot of scientists were tending to do study on men because it's almost a bit like having mice, right? They're also simpler than human beings, that men are also simpler than women because all of these changes make it harder to... Yeah, you're not controlling for menstrual cycle or stage of menopause, hence why you can cut in half at least the amount of people you need to recruit.

So bringing back to this question about how does this play, how are all these hormones playing into this question of fat and what's going on? We haven't excluded men or women from research because we wanted to. It just made the data much cleaner by really focusing only on men because they don't have as many nuances, right? So I brought that up again just because there's so much that we don't know. And I think that as we begin to really beautifully study women across all of these nuances, we're going to learn so much more about women's health that we don't actually know now.

So we started by talking a little bit about estrogens, right? So if you hear me, I'm using a plural, estrogens with an S. It's estrogen with an S. It's because it's a family of hormones. So it's not just one hormone. It's not just one hormone. And yet, a lot of times, whenever women are talking about estrogen, they're just talking about one of the estrogens. The show you're listening to right now that's providing you the latest evidence-based health and nutrition information from the world's top scientists, while making it takes a lot of time, we think it's well worth it, all in the name of improving your health. All we ask in return is

this, send a link to this podcast to someone you think would benefit. And if you haven't already, click follow this podcast wherever you're listening right now. Okay, let's get back to the show. And so how is this affecting what's going on with our fat and where it's being distributed? Right. So my research was always on 17-beta-estradiol. It's the one that helps make those spandex fat cells. It also influences our metabolism because it binds to a certain receptor that I've studied a lot. It's estrogen receptor alpha. I know that's science-y as well, but if you just think of it as a lock and key, a 17-beta estradiol is the key.

It sits into the lock, which is this estrogen receptor, and that's what I've studied. And I've been very, very specific and granular with respect to my knowledge of that lock and key system. That lock and key system, I know, influences the fat cells as well as regulates metabolism in the brain. And we have those locks, so those receptors all over our body, don't we? We don't just have them in our fat cells and regulate metabolism, which is why I think postmenopausal women have such varied symptoms. And so something I was really excited to ask you, and I knew you were coming on, was about hunger. Because we hear women anecdotally say, oh, I'm going through the menopause, I'm eating the same,

but I'm feeling really hungry. Do we have receptors as well that impact our feelings of hunger and fullness? Absolutely. Those same receptors are located throughout the brain, which influences our ability to feel satiated or full, as well as hunger. It also changes our perception of pleasure. Those estrogen receptors are located all over the brain. So as our hormones start to change, those receptors are like, wait a minute, I'm missing a hormone. And I think that that's related to changes in overall appetite, mood, as well as food intake. So you've got the declining estrogen that occurs during perimenopause, although not in a smooth fashion, you're in a state of hormonal chaos. Yes. In some cases, it can be long. In other people, it's not quite as long, right? So

again, when I was at this symposium just recently, I wanted to take all women who perhaps went through menopause at 45 and compare their signs and symptoms versus someone who went through menopause at 55 or 65. Again, I think if we start to learn from women's experiences and we more tightly group them, we might learn so much more. And are they different? Would you expect that those are different depending upon when you go through menopause? Absolutely, I think so. But we don't know. That's amazing. So nobody knows the answer to what sounds like a fairly straightforward question. Easy question, right? And even when, again, at the symposium, one woman still had one ovary. It's like, oh, how about her symptoms? Are they the same as someone who has lost both ovaries? Or again, I think as the more granular we become in asking these really important questions,

the more we'll be able to help women's health. And we're asking these now. We're asking these in our ZOE Predict program research where we now have nearly 150,000 people have completed this. Large proportion of women, 50% post, 50% pre, and a large portion of those perimenopausal. So we can be collecting that kind of data based on the onset of symptoms as well, which invite me back in a year and Debbie in a year. If you just listen on audio, you can see how excited both Sarah and Debbie are looking, which is really cool. Can I just ask a simple question? Because I just want to make sure I'm understanding the link back that I think the two of you have got. So you're describing both the estrogen is both changing, I think, just regularly on a sort

of monthly cycle before menopause, and then this sort of slow decline during perimenopause and falling away. How is that linking back to the topic that we're talking about before about weight distribution? What is the shift in estrogen doing? We know, I think, on other things that it has lots of impact, but how does the idea it has impact on where your fat goes isn't obvious. Could you help me to understand? Well, first of all, let me address that by saying reasons that we don't necessarily fully understand, but the fat that gets in around your belly after menopause,

that's a place where you're actually making estrogen. Believe it or not, I often think of the belly fat that happens after estrogen as your third ovary. As your ovaries stop secreting and making estrogen, you actually have the ability to make estrogen within those fat cells that are in and around your belly. I just want to make sure I've got that because that's crazy. So what you're saying is that you start to lay down this fat as a woman around your belly

and it starts to actually make this hormone that is no longer being made anymore from your ovaries. Did I understand that right? Absolutely. Have we known that for a long time? We have not known that for a long time. Obviously, it's been happening for all of humankind. But scientists have only just recently discovered this. Exactly. And why that happens only within those fat cells, I don't know.

Am I making it in my belly fat as well? You're making a little bit of it. There is an enzyme, a factor that actually can convert testosterone to estrogen. Then that happens within those belly fat. Are women doing this more? So this is some sort of post-menopause change that women are switching on. It's not just that everybody who has belly fat does it in the same way. No. I think what happens is that the body must sense the fact that there is less estrogen. And so it ramps up its own ability to make estrogen. And that's where we make it is within that belly fat. Now, again, I don't's where we make it is within that belly fat. Now, again, I don't know why we make it there, but we do. And so there must be a very important biological reason that we do. But what I don't know is as you're making it there,

does it get into your blood and then circulate throughout your entire body, right? So yes, you're making estrogen within those fat cells that are in your belly after menopause, but does it then get into your brain? Does it then get into you or the receptors that are on your muscle? I don't think we know that. And I think that's a really important point because I don't think we want everyone to go and use putting weight around your belly as a way of reducing menopause symptoms. And certainly from our research, we found that people that have more weight around their belly and have a higher waist-hip ratio actually have worse symptoms, which may answer partially that question that maybe it isn't actually getting into the bloodstream

in order to reduce some of the symptoms you get postmenopausally. I couldn't agree with you more, right? So I think that more in this case is not better, right? So I think that some production of estrogen within those fat cells must be really, really important. But I agree with you. I don't want people to think, ooh, having a gigantic belly with postmenopausally, I'm making all this extra estrogen. Okay, that is not part of the problem, not part of the solution. But I think what I want to do is I want people to embrace it a little bit, right? I think that women, as we transition and we see this shift, I want people to understand—

That's just an inevitable shift with these hormones. And so these hormones—I just want to make sure I've got this very simple. The shift with estrogen is basically somehow telling your body to start to put the fat somewhere different than before. Exactly, right? That's at the simplest level. Simplest level. So that as your two ovaries are stopping making estrogen, your belly starts to, and we all are going to do that. So pre-menopause, you're seeing these fluctuating hormones. So does that mean that as a woman, depending upon the period in your cycle,

that actually you would be laying down fat in different places? Great question. The answer is that we have so much estrogen that's circulating around, even though we're going into like little peaks and spikes, it still is predominantly going into those hips and thighs. Because the overall level is still much higher. So there is this fluctuation, but overall it's still so high that it's all being pushed out into these healthy places. Exactly, exactly. And again, done by design, that's exactly where we want to place it because it's so healthy there. But yes, so new measurement that we've been able to assess. Before, it was really difficult to look at the actual amount of estrogens that are within tissue, and now we're starting to pay more attention and we can actually assay that, look at it very

carefully. So I think the more we learn about that, the more we'll learn why it's there and whether it's a good thing, how wonderful it is. I think there's so much more that we need to know. I think a really interesting way as well of kind of bringing it home to people simply about these changes that happen is that we see, again, from our own research that men and women are really different up until the menopause. So all of our data shows that men have the higher visceral fat that you talked about. So the fat around the belly, a higher waist-hip ratio. And, you know, women are there plodding along at quite a low level.

And then we see as soon as they hit the perimenopause and then postmenopause phase, suddenly they jump up to men. And what also happens at the same time, as well as their body shape changing, from our own research, we see loads of risk factors change as well. So it's not just the fact that, oh my gosh, you know, I've got this fat suddenly around my belly. We also see that women who were doing really well prior to the menopause compared to men, they had lower blood pressure, they had better insulin sensitivity, they had lower inflammation, they had lower blood lipids. So cholesterol, for example, the fat cells start to go up, but also we get this sudden increase in risk

up to the level of men. So suddenly they're the same as men in terms of higher blood pressure, higher inflammation, higher cholesterol, and reduced insulin sensitivity. Big changes to the way they respond to food as well, right? Yes, we see that as well. We see this really clearly in our data where, you know, they might be able to tolerate eating a lot of fat or have much lower blood sugar spikes sort of shift in that decade for many women as well, which has a lot of impact on how they'll respond to food. Yeah. And I think what's really important to mention as well, this isn't just age related. So in the Zoe Predict menopause study that we published, we actually took an age-matched group of people. So we took a group of people, some were male, some were premenopausal, and some were postmenopausal, and we matched them for age. And what we found was that even when they

were age matched, that the postmenopausal women fared far worse in terms of where their fat was distributed and all these other risk factors. The premenopausal women that were age matched to the men were actually very different, even though they were the same age. Yet the men who were age-matched to the postmenopausal women behaved really similarly. Now, is that all due to these fat cells, or do you think it's estrogen acting as well on other factors? I think it's estrogen acting as well on other factors. I think definitely the fat distribution is having a role for sure, but I think estrogens, they have so many effects throughout the body that as those levels change,

I think that's when you start to see disease risk increasing. And I think, again, we talk about estrogen typically when we're talking about one, but then I think it's also the estrogen to testosterone ratio. Yeah, I think it's so complicated because it's also age-related. And disentangling this from age is a real challenge. We often use twins with our research that we've been doing at Predict because Tim Spector, who's one of the co-founders at Zoe, runs the Twins UK cohorts. This is a group of over 15,000 twins, one of whom was taking hormone replacement therapy in the form of estrogen and one of whom wasn't. Okay, so these are identical. That's me, they're basically like clones.

Yes, they're the same age, obviously. And what we found was that by those that were taking the hormone replacement therapy, they actually had reduced risk of all of the factors that we've just talked about, including reduced fat around the belly and blood pressure and inflammation, etc. And I think that's the best way of actually illustrating, you know, it isn't just due to age, that there is this direct impact of estrogen on what's happening to us. Oh, I love that study. Debbie, just before we get on to the actionable advice, which I know we really do want to talk about, I just like to make sure we understand this thing about the weight gain, because I think you've talked a lot about changing distribution in fat, right? So it was going on to your waist and hips, and now it's going on to your belly, but that sounds like it should

still be the same amount of fat. But I think lots of listeners have written in lots of questions saying, well, actually, what I'm experiencing going listeners have written in lots of questions saying, well, actually what I'm experiencing going through menopause is weight gain. What's going on there? And could you explain a little bit what's going on with these fat cells as this weight gain is going on so that listeners can sort of just picture what's going on? There is definitely some weight gain that occurs. I think we are now learning more about the fact that because estrogen increases your metabolic rate, the rate for which you burn calories and food, that as your estrogen levels decline, then you're actually burning fewer calories. And that oftentimes is associated with the weight gain. But again,

I'm so adverse to looking at the actual number on the scale. I want you to feel healthy and love your hips and thighs and where your fat's stored and sort of back away from that specific number. Yeah. And I think that's a really important point because it goes back to the point I made earlier about hunger as well. And so lots of people my age are saying, you know, I'm eating the same, I'm feeling hungry all the time, I'm moving the same, but I'm still gaining weight as well as where it's deposited. And so I think it is about being a bit more forgiving to ourselves. It comes back to it's natural, it's going to happen. Can we do it gracefully and as healthy as possible? Yes,

we can. But I think starving ourselves or trying to fit into those jeans that we used to wear when we were in high school, that might be unrealistic. And let's not beat ourselves up about that. So something also is going on with men. Is that related to anything to do with hormones, or do we understand what is going on there? They have a large amount of life changes. I think there's probably moods and other changes that men go through that I think that men have been less vocal about that. I think it'll be something that, again, we'll learn much more as more people talk about what's going through either their mental or their physical changes that they're actually seeing as they age. But again, it's difficult to separate what's happening with your hormones versus your aging because oftentimes they

happen at the same time. But that's why your studies are so beautiful is to try to dissociate or untangle the age from what is actually happening with your hormones. There is also, you are saying that for men also, there is definitely some shift in the way that weight is being distributed and the weight gain is of becomes easier or harder to fight as you're older. This, again, is not just an illusion. Absolutely. I would love to switch to talking about actionable advice. A lot of listeners are saying, okay, I've hung on for a long time listening to all this science.

That's great. Now, I'd really like to understand what can I do about this? And so I think we had the largest number of questions we had from our community were actually saying, once I've been experiencing basically this shift in where my body fat is distributed, what can I do about it? Well, I think first of all, being forgiving, understand that it's a natural biological shift. I think also making sure that we're eating right and still doing our exercise. I think that that is the health message doesn't really change. I think it just becomes more important because I... And does the exercise have an impact on this? Absolutely. And that really does affect sort of the redistributing because I think lots of people will be listening

to this and potentially, you know, a bit surprised that that makes any difference to your fat distribution rather than just impact your health. I would say that you're still going to have a shift. It's still going to happen, right? But I think that what the exercise does is it helps maintain our muscle mass. And the more muscle we have, the higher our metabolic rate. So I just am a huge advocate of weight-bearing activity. I also love for people to switch it up. Don't just get stuck in the same routine, right? You know, I think that

our bodies are such incredible machines. They get very, very comfortable with one activity, you know? So if you only go to the treadmill and every day you run for an hour on the treadmill, now maybe as you're starting to transition, mix it up a bit. And I think something, Jonathan and Debbie, that I get asked a lot is what foods can I change? But what we do know from our own research is that how you metabolize the food is actually quite different depending on the phase of your menopause, whether you're pre or post-menopause. So what we find is that post-menopausal women who we know are more insulin resistant actually have a higher blood sugar response to a carbohydrate-rich meal.

And so one recommendation we can make, given that we know that that's not best for our health, we can say, actually, can you be a bit more mindful about the types of food that you're eating? So be a bit more mindful about having refined carbohydrates. So your white breads, your white pastas, your white rice, you know, your sugary foods. And actually another finding from the Zerimenopause study was that postmenopausal women, and again, this is an age match cohort, were actually eating a lot more high sugary foods, which is interesting. And this could be all related to, you know, you said the receptors in the brain that make you crave different types of food. So you're craving more of these sugary foods, which is interesting. And this could be all related to, you know, you said the receptors in the brain that make you crave different types of food. So you're craving more of these sugary foods and they're also being metabolized more unfavorably. So whilst there is

no silver bullet, I think it's really a time that we can say, yeah, just be a bit more mindful about those kind of quick fix foods. I love that. I think that being more mindful is spot on. I think the other thing too is that oftentimes we reach for really refined foods, the processed foods. And there's so much data coming out right now indicating that processing of foods, even if you eat the same number of calories, but all of your calories are coming from processed foods, it's so much more unhealthy, the processed foods. So I think that as we transition, if we can go back and eat a more healthy diet that is not processed, going for the fresh fruits and vegetables, actually making your meals either at home or making certain that you're utilizing fresh ingredients will do a world of good, especially

as we're transitioning. I think that's the most important message for people to take home is that actually enjoy cooking again. Yeah. And I think that's really important because we know it interplays with all of the stuff we've been talking about. So we know that ultra-processed or heavily processed foods actually stimulate our hunger hormones even more. So it means that actually we feel more hungry.

And there's some great evidence showing this as well, that on average over a day, if you're on an ultra-processed diet versus an unprocessed diet, you can consume 500 calories more than if you are having it unprocessed. And this is all related to the hunger signals as well as other factors. And so if our hunger signals are more heightened in menopause and our fullness signals dampened, then again, this is a time to really pay attention to the level of processing of the food. Absolutely. And I think it's just staying away, even as you were mentioning the carbohydrates and having the insulin spikes, going back and eating high fiber foods that are real fiber, eating a big potato, a broccoli, eating them again in

their more natural form, I think is so much more healthy, especially in that transition. Amazing. What about supplementing estrogen? So, I mean, you've talked a lot about how this decline in estrogen is having this impact. Would that stop a lot of this redistribution? It does, right? So, there's some beautiful data on that as well. And the time for women to begin having the discussion with their physician about hormone utilization is before they go through menopause. I think there's been so much confusion about hormone replacement therapy, whether it's good for you or bad for you. I think that the research predominantly suggests it's great as long as you do it at the right time. It's the women who went on hormones 10 years after they

went through menopause where we all of a sudden start to question whether it's beneficial for them or not. But if you're in that process of transitioning, you have irregular menses or irregular periods, you're in that age zone of 40 to whatever, that's the time to think about going on hormones. And I think that that's a really wonderful discussion to be able to have with your physician or a menopause therapist or whoever you feel comfortable having those discussions with. And are there any options if either you don't want to do that or you can't take hormone replacement for various reasons?

There are plant estrogens that we can take, that our diets can have more of the soy and more of the phytoestrogens. These are estrogen-like compounds that we can get from our foods that we eat, oats and sprouts and soy, a lot of soy. They are estrogen-like compounds that you can get from the foods that you eat. They can be beneficial. They're not 100% perfect, but they will provide some benefit. This is where it becomes quite tricky. So in a lot of East Asian populations, they actually have a lot lower prevalence of postmenopausal symptoms, including visceral adiposity, so their belly fat. Soy, oestrogens are just part of their daily diet. So they get above that kind of threshold dose. So you need to make a big shift to a diet that looks a lot like you might be eating in Japan

or something like that. You can't just eat edamame beans once a week. No, that won't give you the required dose. And so this is one of the few times ever I might suggest someone consider taking a supplement. So a kind of pill that you can get that has these, they call them soy isoflavones. But again, you need to make sure you're getting the right amount. So getting above 15 milligrams of a particular one, which is called genistein, and it's above that threshold that it seems to have a beneficial effect. The evidence that showed a negative impact of hormone replacement therapy previously that's caused a lot of the confusion, and Debbie touched on this, as well as starting

it in older individuals, it was also a very different kind of hormone therapy that we use in the UK. So in the UK, we use something called transdermal HRT, which is basically either a patch or a gel. So it goes through the skin. And in the States? We've now, we're starting to have more of that, but for the longest time it was a pill. And so that became very concerning because it goes back to those estrogens, right? So you take a pill, it gets broken down through your liver, and all of a sudden you get these different estrogen-like compounds that aren't that primary 17-beta estradiol. And we don't know what all of that did, but the patch, the transdermal,

so much better, so much healthier. So I applaud those of you in the UK that you have that as an option to you. And that is where things are transitioning across the states as we speak? Exactly. I believe in Canada as well, as they have predominantly a transdermal hormone replacement therapy, but it's so, so incredibly important to do it that way. And I think it's really important to say to female listeners that are contemplating HRT, because I get asked this daily, that there are still a lot of healthcare practitioners that are cautious about HRT because of the evidence using these old oral HRT capsules, but the same negative effect does not hold out to the transdermal. So I would be persistent if this is a route you want to go down with your healthcare practitioner.

If you're a woman listening to this and you are not perimenopause, is there anything that you should be doing now that is, I guess, setting you up right for the future? Other than I think your message that you should be more relaxed about the fact that your fat is probably in a healthy place than you have realized before this podcast? Obviously, you want to continue your activity. I think that's just, we are unfortunately a very sedentary society. And so I think that what you can do as you are approaching that age is just making sure that you have some beautiful muscle mass and just keeping your activity up and eating a very healthy diet that is not filled with processed foods. I think those are the best things that

you possibly can do to help really reduce really negative symptoms that happen during that menopausal transition. But be kind. And it sounds like that's actually really the same message for men throughout our life, is it? And in a sense, the same advice you were giving to women sort of before perimenopause is about exercise and diet. Absolutely true.

And so I think, you know, one of the other areas that I think more exploration will come will be estrogens also work on the gut microbiota. we see that it's potentially mediating some of the unfavorable effects of menopause on factors like inflammation, on the distribution of the fat tissue, and on some of the other... Mediating means reducing? What does that mean? So what we know is that the menopause, for example, is associated with unfavorable changes in circulating inflammatory molecules. And what we can do is look at, is there a role that the microbiome is playing? What it seems is that the microbiome is actually playing a role in how the menopause impacts inflammation, body fat distribution, and other factors related to

metabolism. So one hypothesis is, which I think Debbie alluded to, is maybe we can use diet to modify the microbiome and maybe this will also help in some of those unfavorable effects that menopause has on our metabolic health. Amazing. Look, I think there's a million more questions we could ask, but we're definitely at time. I think we started off by saying this amazing thing that not all fat is unhealthy. And I think if I take one thing away from it, it's this idea of like love your hips and thighs. Actually, this is not doing you any harm. And in fact, there may even be some evidence this is actually, it's not just sort of dormant source of energy either. They may actually be active, you know, metabolism is doing things for you. Then also there's a big difference between men

and women in terms of where they store fat, that actually women are storing fat in much better places, like the spandex fat cells that are expanding and shrinking, whereas men are tending to store their fat in their belly, near all of these organs. We use this word visceral fat some of the time, which I think we've sometimes heard other people talk about in this podcast as being really unhealthy. That's all good. The issue is that as women go through perimenopause and menopause, this shifts. And this is because of these big changes in hormones and reduction in estrogen. And women start to store their fat more like men starting to put it into their belly. So this idea that you start to get belly fat in

menopause is just a real scientific fact to be accepted rather than something to feel guilty about. And the real issue from your perspective is, again, it's nothing to do with how this looks. It's just that this is less healthy, that this fat is linked to a lot, ultimately, of disease risk, things that can lead to diabetes and heart disease. And men in general are at higher risk of all of these things because they're putting their belly fat there. But then, you know, through perimenopause and menopause, women start to have these same risks. That BMI is not your best measure. Ideally, you would get sort of like a body scan. And unfortunately, that's not yet cheap enough that, you know, everyone can do that regularly. But waist to hip ratio, and we'll put on the show notes a way to do this, is a better

way to understand sort of where you are. That as you lose that estrogen, it's not just redistribution, but there is some weight gain that is going on. And this is true for women. It's also true for men through time. And so this means you do have to worry more because of the way this starts to get linked to your health. But there are things you can do. Firstly, be forgiving, which I thought was a brilliant message. Like the reality is your body has changed. You can't expect it to just work the same way as when you were 20. Exercise is really important. So is diet. I think, Sarah, you talked about the fact that there's like a big change, particularly if you're a woman going through

menopause in terms of how you deal particularly with things like blood sugar and that actually at the same time, your hormones are pushing you to eat more things that are high sugar. So if you can be really conscious of that, you can potentially make quite a big difference. Some very good news, I think, for women going through this, which is that you're saying hormone replacement can really have an impact on this weight gain and redistribution. there's a shift towards it being delivered no longer through a pill, but through a patch, which has, I think, been true for quite a long time in the UK. But for people who are listening in US or various other countries, this may be much, much newer. There may well be food options, but I think Sarah cautioned that if you're just eating a small amount of soy, it's not going to get you there. So unless you're eating a lot, you may want to think about supplementation.

And if you're listening to this as a man, a lot of this is relevant for you as well. And the emphasis is really like this sort of exercise and healthy diet through the period because actually you're sort of fighting this from the beginning, right? So if you're listening to this as a man in your 20s, as I rather discover as a shock in my 40s, you may already be starting to lay down fat in a bad place and just not even aware of it. Love it. Wow. Wow.

Fantastic. This was fascinating. Thank you so much, Debbie. And it sounds like there's a lot of ongoing research into sort of how these hormones are impacting us. So I hope that as that progresses, you will come back and keep us updated. Oh, I would absolutely love it. Thank you so very much for having me.

It's been spectacular. Thank you, Debbie. And for coming so far. I'm never going to complain about my hour commute to the studio again. Wonderful. But thank you so very much for having me. It's been spectacular. Thank you, Debbie. And for coming so far. I'm never going to complain about my hour commute to the studio again. Wonderful. Thank you so much. Thank you.

Thank you very much. Thank you, Debbie and Sarah, for joining me on Zoe's Science and Nutrition today. We talked about the link between our body fat and our health and why our body shape changes as we age. We also learned what this means for our risk of poor health and the our body shape changes as we age. We also learned what this means for our risk of poor health and the steps we can take to prevent diseases. We discovered that good nutrition is key for a long and healthy life. If you want to understand how to support your body with the best foods for you, then you may want to try Zoe's personalized nutrition program. You can learn more and get 10% off by going to zoe.com slash podcast.

As always, I'm your host, Jonathan Wolfe. Zoe Science and Nutrition is produced by Yellow Hewins Martin, Richard Willen, and Tilly Fulford. See you next time.