Pod Insights The Diary Of A CEO with Steven Bartlett Moment 107 - Why Counting Calories Doesn't Work: Tim Spector About this episode In this moment Dr Tim Spector unravels the myth of calorie counting for health and weight loss. Dr Spector discusses how dieting is not just a simple case of tracking calories in compared to calories, as it is nearly impossible for even professionals to accurately count calories. Furthermore, just as people and their lifestyles are not the same, neither are calories. Calories from either quality whole food or ultra-processed can have radically different impacts on your health. Instead of obsessing about calories Dr Spector believes you need to be focused on the quality of your food. Listen to the full episode here - https://g2ul0.app.link/uqBbGwMhlzb Tim: https://www.instagram.com/tim.spector/?hl=en https://tim-spector.co.uk Watch the episodes on YouTube - https://www.youtube.com/c/TheDiaryOfACEO/videos
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Transcript Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.
0:02 Steven Bartlett? One of my friends is a prolific calorie counter. And you know, he eats a lot of Domino's pizzas. He listens to this podcast, he's going to know exactly, he's going to know that I'm atting him. He eats Domino's pizzas all the time. He eats like a real processed food diet, but then says to me, it's all about calorie counting. Now, with all due respect, friend, he's never managed to, I shouldn't say that, but it's not necessarily worked for him in terms of the goal that he's set himself. So when I was reading about your view on calorie counting in your book Spoon Fed, it was, I screenshotted it this morning and sent it to him and I said, you are a bullshitter.
0:46 Steven Bartlett? That's what I said in the message and we had a good laugh about it this morning. But what is your view on calorie counting and this idea that we can, you know, weight loss or being healthy is just about having a calorie deficit?
0:56 Tim Spector? It's complete nonsense.
0:58 Steven Bartlett? Thank you. I will clip that and send it to him.
1:00 Tim Spector? There's never been any long-term study showing that calorie counting is an effective way to lose weight and maintain weight loss after, you know, the first few weeks. So yes, very strict calorie counting, if you deprive yourself for a few weeks, you will lose some weight, but even if you're successful, your body's evolutionary mechanisms will make you hungry and hungry every week you go by where you're depriving yourself of energy. Your body will go into sort of shutdown mode, your metabolism slows down, so you're not expending those calories.
1:38 Tim Spector? And inevitably, I'd say more than 95% of people will go back to their baseline and many go above it. They rebound back if they're doing this, this style of calorie restriction. Now, calorie counting is a part of that, so people try and say, okay, I'm not going on a dramatic diet, but I'm going to just try and reduce by 10% my calories in a day, which in the old theory was supposed to make you lose weight. Well, it's virtually impossible, even professionals, to count calories.
2:12 Tim Spector? And because uh they're not very accurate for a start, everything on the packet, you have to weigh everything. And in restaurants now, we're supposed to have these calorie counts, they're plus or minus about thirty percent because portion size makes such a huge difference to it. It's it and it's been shown in the US to be a worthless exercise anyway. So you can't count them going in, you can't really count your metabolism going out either. We're all incredibly different. You know, your friend's probably been told two thousand five hundred calories is what he's allowed. Hmm. Well, that's an average, uh but it doesn't mean it relates to him. My average is much
2:55 Tim Spector? lower when I tested it. So everyone is an individual and this is another thing we need to move away from this one size fits all guidelines. But I think more importantly is that the whole calorie counting assumption means that it doesn't matter what form that calorie is, it has the same effect in your body. Therefore, whether you're cutting out fat calories or carb calories or, you know, low calorie sodas or whatever it is, it's it's going to be fine. But we now know that's not true. Um and there's several science experiments which now absolutely nail that. One was um but in America where they gave
3:37 Tim Spector? people identical meals um for two weeks in a sort of enclosed semi-prison. And one was homemade and one was ultra-processed, both identical calories, macros, the same. The group with the ultra-processed foods overet by about two hundred calories every day. They kept coming back to the buffet for more. Okay, so yes, the same calories, but the effect on the body meant they were hungrier. Why is that? We don't know for sure. It could be. That those chemicals in the ultra processed foods affect the gut microbes. And they then send signals to the brain saying, eat more, this isn't a natural.
4:19 Tim Spector? You know, this is a really weird chemical. It's doing something weird to me. I'm producing something weird in exchange. It could be they get absorbed much quicker. So you get a big sugar rush. And you know, the nutrients get in to your body in a way faster than they should do in nature. And so your brain doesn't have time to say, I'm full. It normally takes 20 minutes or so to to get that fullness. Um, or, you know, it it. So it could be the matrix of the food. It could be the chemicals in the food. It could be its effect on the gut microbes. Um, but it also could be things like your sugar spikes. So in the Zoe predicts studies.
4:59 Tim Spector? Where basically we've given now 50,000 people um in the US and the UK, the same foods at the same time. Same time of day, everyone's got these muffins. We show that people, um. One in four people who have these muffins and are wearing it, we wear glucose monitors, which tells you. For two weeks every what's happening in your glucose. One in four people get a real sugar dip. Three hours later. So this is where you you rise in sugar, which is normal. And then as it comes down, it goes below baseline, but only in one in four people. And when that happens, those people end up uh overeating their next meal.
5:41 Tim Spector? And during the day, they feel more tired, more hungry. That's this, the sort of 11 o'clock slump, if you like. If you've had a carby breakfast, some people feel that, others don't. And what's really interesting is that so one in four people eating an identical muffin of identical calories. Will then overeat by this, you know, another 10% that day. So you can see how that just blows the calorie um idea out, that the calories in equals calories out. Everything's the same and.
6:13 Tim Spector? And the third thing is that ultra-processed food says it has the calories that's equal to the whole foods, but often they don't account for the fact that it's ground up, it's highly refined. And so if you take like almonds or something like this, they might use ground almonds. And you compare ground almonds to whole almonds, there's perhaps thirty percent less available calories in the whole almonds than there is in the other ones. So the whole thing is a complete nonsense and it's there because the food industry wants you to focus on the calorie, the fat content, sugar, so you don't have to think about the quality of the food. And it's something that they can control very easily,
6:58 Tim Spector? get their profits higher, keep adding stuff to the product that's synthetic. When we know that a lot of things they're adding are harmful for our gut microbes, so that the artificial sweeteners are harmful, the glues, they stick the foods together, the emulsifiers, some people react quite a lot to those and they cause problems. So the whole thing is like this giant camouflage. And that's, that's really one thing I'm, you know, it might probably my number one bugbear is to get people to see the light, stop obsessing about calories and start thinking about food much more as quality and what it does to your body.
7:41 Steven Bartlett? Quality food. What is quality food in your definition of the phrase?
7:47 Tim Spector? It's the opposite of ultra-processed food, which is whole food, which is made with, from the original ingredients of plants, mainly plant-based, but it's not exclusively, that contains all the nutrients that those, those plants produce, without it being stripped away, or boiled up, or highly pressurized, deformed. And so they have to add in back those nutrients. So, you know, it's things in their pure form. So it's, it's nuts, it's seeds, it's, it's grains that haven't been ground up superfinally. It's all the amazing plants and fruits and vegetables that we've got. They, they're healthy foods, but, you know.
8:33 Tim Spector? It's it's not straightforward. Yes, I've got this list of ten superfoods. It's it's understanding that many foods that you know, are healthy for us, most of them are, in their in their original form. Berries, nuts, um virtually every vegetable is healthy for us if it's in that original form. It's only because we've we had to learn to preserve things, we had to do trickery to make, you know, margarine and things with chemistry that we've moved away from that. But, you know, going back, you know,
9:12 Tim Spector? olive oil, for example, is is a great example of something that be vilified often because it has lots of fats in it and you know, certainly I was told the Med Trains, they have they have olive oil on everything. It's horrible. It's all fatty. Turns out that's that's a perfect, you know, it comes from the olive. The good stuff, extra virgin olive oil, has very little done to it. And that is a a good, healthy, quality food. But it can be refined. You can take that and you can keep refining it. Um. You can take corn on a cob as an example, and then you, you know, and then you've got, I don't know, uh, tortilla chips or something down the other end is which bears or cornflakes, which bears no resemblance
9:56 Tim Spector? to the original, and they're all versions on a spectrum.
10:02 Steven Bartlett? God, it's so confusing, you know, because what you've said to me is, you know, based on research and studies, but then when I go to a supermarket labeling, even I was just thinking in cornflakes. I think I grew up thinking cornflakes were healthy because it says corn in the title. You know what I mean? And it's and when you're trying to navigate, I was just thinking if I'm going down an aisle now, hearing what you've just said, that that quality food is food that is not ultra-processed and kind of resembles its original form. When you walk down the aisle in the supermarket, everything is trying to pretend that it's good. So how do I know what is good? I mean, I can go to the vegetable aisle and I can say, okay, that looks like a cabbage. It looks like no one's messed with that. There's been no study done on that to, it hasn't been through a laboratory. But how do I, like, if I'm in an aisle tomorrow, how do I know what food is good and what is not?
10:46 Tim Spector? Well, you've said the first thing, if it's not in a package, you're pretty sure it's good. Okay, so if it's concealed in some package that's got, you know, happy children and signals of vitamins in it, that should be a warning sign. You know, the more they have to advertise the food and say what its additives are and everything, the more you should be wary about it. The number of ingredients is another pretty good sign. So once you get over 10, particularly if there's lots you've never heard of, you wouldn't find in your kitchen, you should also be wary that that is ultra-processed food. Anything that says low calorie, that says, means they've had
11:27 Tim Spector? to add in lots of artificial sweetness, or protein extracts, or something else, is also a big danger sign. Low in fat means they've replaced the natural fat with something else that's cheaper. And these are all warning signs, you know. And, you know, you take breakfast cereals. I mean, I used to, I used to eat lots of breakfast cereals. I was brought up on them, highly sugary stuff. And then I thought I was being healthy when I moved to Moosley's and Posher, Posher stuff. But actually, when you still, you know, that appearance of healthiness, it's still got lots of additives in it. It's still got lots of sugar in it. It's just, and
12:14 Tim Spector? those cereal packets have added vitamins in it, but they're often in a very poor form. I did the experiment once where I took some cornflakes or Special K, I can't remember, that says had added iron. And if you mix it up, you can put a magnet on it, you can get off the iron filings. They're so cheap that they're just added to tick a box saying it has iron, but they don't get into your body or do anything. So anything that's got These things added with this in it, low in this, is a sign that they're obscuring the quality of the product. So it's, you know, but it's a lot of brain, you know, we've been
12:54 Tim Spector? brainwashed for years and decades in this. And, you know, I was as well as a doctor, you know, I should know better. And yet, I've completely changed my seven, two of my meals completely. So I've gone from having muesli with low fat milk and an orange juice and a cup of tea. Because I did, you know, I started doing these tests for Zoe, I found out that gave me a massive sugar spike. And it was a terrible way to start the day. And I got these, you know, dips at eleven o'clock, to a high full fat yogurt, nuts, seeds, a few berries,
13:34 Tim Spector? and I never have orange juice. That's on my, that's a really unhealthy drink for everybody. And I have lots of black coffee, which I now know is good for me. So that's totally different. I changed my lunch for at least ten, fifteen years. Um, when I got in the hospital, I was having a hospital lunch, which used to be in the canteen, then it was Marks and Spencer's, got a healthy looking sandwich with brown bread, sweet corn, and tuna, and a smoothie, in a little bottle. And that gave me a massive sugar spike. And I wouldn't have known that.
14:15 Tim Spector? And I was told that should have been a healthy thing to eat. So, you know, there's, there's general rules, but also there are specific rules. And this whole idea of individuality is coming in. So it could be that you could, you might be fine on that. Don't know. Um, I was very annoyed because when I started, we were starting doing this testing for Zoe, I had all these spare kits and I gave my wife one as well. And we sit down and she's French Belgian and loves croissants. And so we'd have croissant each. Mine would shoot up. She had no change at all in her, her, her sugar, which was really annoying.
14:53 Steven Bartlett? Yeah.
14:55 Tim Spector? So, but it also brings, brings home the fact that, you know, Everyone loves simplistic rules, but you can only get so far with them. You have to start experimenting yourself and see what works for you and not just take everything for granted. And that's really the, that's the whole essence of really, you know, setting up this personalized nutrition, research and Zoe and everything else. But on top of this general advice about changing our idea of food, I think, because I think they do go hand in hand, that if you realize there are these individual differences, you realize it's not as simple as you've been told. It's not that fats are evil. It's
15:37 Tim Spector? not that calories are bad, you know, it's, it's much more nuanced.
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