ZOE Science & Nutrition - Recap: The misunderstood function of fat | Deborah Clegg

Episode Date: February 11, 2025

Today we’re discussing fat. It’s a word that carries a lot of weight. It’s a source of social judgment, a driver of insecurities and a tool exploited by companies in targeted marketing campaigns. It’s no surprise that a recent study found over 40% of people in the US have experienced some form of ‘fat-shaming’. But do we really understand fat? What it does, how it forms and why its distribution changes as we age. Prof. Sarah Berry and Prof. Deborah Clegg are here to help us answer some of these questions and change our perception of fat. Deborah Clegg is a professor and Vice President for Research at the Texas Tech University Health Sciences Center, El Paso. Sarah is Chief Scientist at ZOE and Professor at King’s College London.  🥑 Make smarter food choices. Become a member a zoe.com - 10% off with code PODCAST 🌱 Try our new plant based wholefood supplement - Daily30+ *Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system 📚 Books from our ZOE Scientists: The Food For Life Cookbook by Prof. Tim Spector Food For Life by Prof. Tim Spector Every Body Should Know This by Dr Federica Amati Free resources from ZOE: Live Healthier: Top 10 Tips From ZOE Science & Nutrition  Gut Guide - for a healthier microbiome in weeks Have feedback or a topic you'd like us to cover? Let us know here Listen to the full episode here

Hello and welcome to Zoey Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health. Today we're discussing fat. It's a word that carries a lot of weight. It's a source of social judgement, a driver of insecurities and a tool exploited by big food companies in targeted marketing campaigns. It's no surprise that a recent study found over 40% of people in the US have experienced some form of fat shaming. But do we really understand fat? What it does, how it forms,

and why its distribution changes as we age? Professor Sarah Berry and Dr. Deborah Clegg are here to help us answer some of these questions and change our perception of fat. 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, it's 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 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? 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 in 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 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 for more quickly? Is it more stubborn around the belly because of these differences?

It is a little bit more stubborn, especially as we age, but 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 our 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. 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- Does the exercise have an impact on- Absolutely. On this and that really does affect sort of the redistributing. Cause 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 you every day you run for an hour on the treadmill, now maybe as you're starting to transition, mix it up a bit. Yeah, 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, your sugary foods. 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, you know, 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. That's all for this week's recap episode. If you want to

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