ZOE Science & Nutrition - Recap: Make the most out of EVERY meal | Christopher Gardner & Sarah Berry

Episode Date: September 2, 2025

Today, we’re asking: What should you eat? This is the million-dollar question, one that we at ZOE have spent countless hours of podcast episodes trying to answer. However, all of this information can be overwhelming, turning breakfast, lunch, and dinner into a daily dilemma. So, are there any simple tips we can keep in mind to reduce the stress around mealtimes? I’m joined by nutrition experts Professor Christopher Gardner and Professor Sarah Berry, who will share their approach to this complex question and offer practical advice on how to make the most of every meal. 🌱 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 Zoe Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health. Today we're asking, what should you eat? This is the million dollar question, one that we at Zoe have spent countless hours of podcast episodes try to answer. However, all of this information can be overwhelming, turning breakfast, lunch and dinner into a daily dilemma. So are there any simple tips we can keep in mind to reduce the stress around meal times? I'm joined by nutrition experts Professor Christopher Gardner and Professor Sarah Berry, who will share their approach to this complex question and offer practical advice on how to make the most of every meal. Christopher, you said to me, you know, before this recording,

like the number one thing people say to you is, Doc, what should I eat? What's the starting point for answering that question? Okay, and I think Sarah's going to be with me on this one. My first answer is, it depends. Absolutely. My next two follow-ups are, please tell me with what and instead of what. And where are you now? So, you know, if somebody says, I'm really thinking whether I should eat eggs or not,

and I say, well, what were you going to have otherwise? And they said, well, I was going to have steel-cut oats or eggs. I said, well, I don't know, what were you going to have the eggs with? I said, well, I was going to have sausage and bacon. I said, oh, okay, so I really think you ought to have the steel-cut oats. instead of that. Oh, I didn't mean that. I meant a veggie omelet. I said, oh, veggie omelet, still cut oats. Yeah, not too bad. Pretty equal. I'm fine with that. Or they said I was going to have a Pop-Tart. I said, oh my God, have the eggs. God forbid you eat that Pop-Tart, right? And so

if you put it in the context of with what and instead of what, they could often answer their own question for you, knowing that part. Yeah. And at Zoe, we often, we often talk about swaps. So it's a simple way of really explaining what you've just, or putting into practice what you've just explained. So we say, okay, this is what you're currently eating that isn't so healthy. This is a healthier swap. So it can be used in the same way, because we have to be practical. There's no point recommending either food that people don't like, like we've already said, but also that isn't used in that kind of traditional breakfast setting or snack setting. This really ties into, there's been a shift in American dietary guidelines. So every five

years, they update the dietary guidelines for Americans. And two or three cycles ago, they made sure to talk about shifts. So for many years, American nutrition was about penalizing. Don't eat added sugar, don't eat saturated fat, don't eat salt. But they didn't tell them what to eat. And a colleague of mine, David Katz, loves to phrase this. As Americans are incredibly clever, you know, they will find an unmeasurable number of alternative ways to eat poorly. Once you ask them to avoid this. Oh, I found another way. That's poor too. Oh, I found another way. Well, that's poor too, because we didn't tell them what to eat. It was easier to tell them to avoid that. What is a good way to eat? Yeah. And, you know, there's different names and different approaches. If I had to ask,

you know, in the three seconds, I would say, whole food plant based. And whole food means just just not the processed and refined things. So you take the wheat berry and you've turned it into flour for bread. Now eat the wheat berry. You've taken the brown rice and turned it into white rice. You've taken the soybean and turned it into soy protein isolate and added it to a protein bar. No, no, you should eat the whole soybean. So that's what I mean by whole food.

And plant-based means you don't have to be vegan or vegetarian here, but boy, people are eating a lot in the U.S. in particular. We eat more meat than any other country in the world. So you don't have to give up all of that, but give up a lot of it and have a plant-based meal. This is where the Mediterranean sort of grain and bean-based dish, which globally have been staples for many, many years in many cultures, partly because they store easily and they're economically feasible. grains and beans are pretty simple food bases to start with, and that's why spices are so important.

So get, you know, Moroccan spices, Mediterranean, Latin American, Middle Eastern, Asian, spice them up. And then you can add smaller amounts of fish or poultry or pork, something in smaller amounts of meat. So the chefs that I work with for this unapologetic deliciousness do something called the protein flip, where the base of the meal is grains and beans and veggies. And then meat becomes a condiment or a side dish or just a small portion on top of that. So to me, that's very Mediterranean and has lots of flexibility for enjoying what you're eating. And in a way that sounds very simple, but I think for a lot of people listening to this, also quite unclear in comparison to diets where based on this idea,

you have to remove this thing because it's sort of killing you or causing problems. Or basically, everything is about calories. You know, you're measuring your calories. So obviously, you're not going to get better unless you reduce your calories because that's what it's about. So maybe we could take those two parts, one after the other. Like, why is whole food better than processed food? After all, I chew it all up and it goes in my stomach.

So I always, I remember discussing this with my children at various points, you know, when it's all messed up. They're like, oh, it's okay. It's going to be messed up. up in your stomach anyway, so you might as well eat it that way. So why is it that we can't have it all nicely sort of processed and prepared by the food manufacturers? We're busy people, and we have to have this sort of whole food thing that you just mentioned. Okay, so I'm going to ask Sarah to help me fill in on this because satiety and satiation are huge factors in all this

that are harder to study than we think. Yeah. And the air-chistophers means how full you fail, because I know you would want us to give a simple term for that. And so this comes up for me all the time thinking, so one of my favorite authors is Barbara Rules who wrote a book called Volumetrics years ago. And it was the volume of the food that was filling people up. And the volume tends to be much higher if it's veggies and beans and grains than if it is cheese or meat or dairy.

And so eating this very satiating meal so that you get full quicker and stop eating and that it's longer till your next meal really helps here. As scientists, this is very hard to study. So I've done a number of studies where I've got diet A and diet B. And what I'd really like to know

is after three months in the study, how hungry were you in March? How hungry were you in April? We don't have any metrics like that. All the metrics for this concept of satiety are, I gave you a standardized breakfast at 8 a.m. It had 600 calories and two hours later, I had a line from starving to very full,

and I marked on the line where I was in between. Okay, how does that work for April? I can't tell you for April. I can only tell you two hours after the standardized 600-calorie breakfast. And so it's actually a harder concept to measure than you would think. I mean, you can just qualitatively say, so how hungry were you? And people give quite a varied response. Well, I have some good news for you.

I'm ready. In our Zoe app, every week we ask people weekly, not just after each meal, how hungry have you felt this week? So we will be able to look at people's diets. But we have also collected data in that old-fashioned way, but where they do on a scale, say, after meal, how hungry they feel. I often think about the health effects of processing also around the idea that you've talked about, like the instead of what.

So what's happening is we're removing some of these great nutrients, you know, the fibre, some of these bioactives that we often talk about as nutritionists, so polyphenols, we're adding in the bad nutrients, the salt, the sugar, you know, the refined carbohydrates, the saturated fat. We're eating these foods more quickly. So not only are they more energy-dense, like you say, filling up our tummy, but we're eating them so quickly that that's another reason our fullness signals aren't getting to our brain in time. And, you know, all of this means that we're over-consuming the wrong nutrients, dare I use the term nutrients, because I know you like me are very food-based, rather nutrient-based, eating less of the good nutrients

and eating in the wrong way as well. Yep. Kevin Hall has done a nice study like that. Again, they were people who were confined and a lot of control was over this, but had an ultra-processed versus a minimally processed and timed how fast they were getting the calories. And much to your point when they're eating the more heavily processed food, they're eating more calories faster. A 50% difference in the rate at which they ate those calories between the ultra-processed and the unprocessed foods, which led to about 200 calorie difference, I think, over the day. And it was hard for that message to get to the brain in time to stop you. So I think you're saying there's like two effects here.

One is that the more processed food, I'm just basically going to eat it. faster. It may even be designed so that I, you know, don't want to stop eating it. So I'm just going to end up consuming more calories. But there's a, the second part, which is you're saying the food is just worse for me when it's been really processed that you're losing a lot of things that now scientists understand are really important to us. And I think, Sarah, you mentioned, you know, like the thousands of chemicals in our food, right? Because most people listen to this are like, aren't there like seven vitamins? Isn't that basically what there is in food? Because you see them, you know, on the great big labels on breakfast cereal, like, hey, this vitamin

and this other one has been added. I've got a colleague named Michaela Kiernan, who approached this in a wonderful way. She said, okay, you know, pick this thing that you think is not so good in your diet that you'd like to replace and try at least five things to replace it. And if you're going to replace it, replace it with something that is as good or better, as opposed to there's a thing I want to get rid of. I tried an alternative and it wasn't as good, so I didn't do it, and I went back. it takes some time.

But once you've put in that time and you've replaced that thing with something as good or better, you have a change for the rest of your life that you made. And that's again, now it's part of your lifestyle, you know, where to shop for it,

you know, how long it takes to make it, you know, what you need ahead of time. And for me, that's why it's important that this is a journey and not an overnight thing. I tried five things. It took me weeks to look for other options.

But now that I've got it, I mean, think of everyone who, regardless of what their diet is, if they were pushed, there's three or four things that they know they like that they could get quickly. And so to tell them, don't do that anymore, have this other thing. Oh, the other thing isn't going to be nearly as quick as a convenient. Of course not. Not until you get accustomed to it. And then it will replace that and it'll work just as well. Now you touched on sort of think the first part there for what you described, sort of whole food, not processed and how, you know, if this food ends up being,

really processed, like one, we just digest it really fast and you get these great big blood sugar spikes. And we talked about some of the negatives on that, I think, over the last few days. And then I think, Sarah, you're also talking about how you lose a lot of things that are stripped out. Could we talk a bit about the other part? So plant-based, which I think, you know, for some people listening, it's like, what does that mean? Like, plants or things in the garden and why is that a good thing? And how does that tie in with the Mediterranean diet you talked about before? Sure, because some of the key things that we came up with from the reductionist days was high saturated fat versus low saturated fat or fiber being good for you. So plants have fiber. Animal foods don't have fiber. Very few plant foods have saturated fat. All the animal foods have saturated fat. So if you just wanted to start overly simplistically, that's a place to start to include more plants in your diet.

And why is the fiber good? Fibre is good for the microbiome. It's the food matrix. It slows the digestion so that the carbohydrates that you are eating that are going to turn into blood glucose appear slowly over time, satiating. It'll help you feel full sooner. It'll last with you longer. This is something we're really interested in as well because we know that fiber is like the party food for the microbiome. as well. And that's where we see the strongest signal. So we see that the association between

fiber and a healthy microbiome is incredibly strong. We know that fiber is one of the single nutrients, and I know again we hate to talk about nutrients, that is associated with improved health. And I think that one of the strongest reasons is because of the impact it has on our microbiome as well as these other mechanisms. That's all for this week's recap episode. If you want to learn 10 science-backed tips to improve your health for some of this podcast's most popular episodes, you're in luck. You can download it from zoe.com slash free guide. Or if you're looking for another episode to listen to today,

why not try a popular episode of Zoe Science and Nutrition, like what to eat to avoid osteoporosis, how to prevent heart disease, or mushrooms as medicine. Search for them on your favorite podcast player. Thank you.