This led to the concept of food calories, which are now used to quantify the energy content of the food we eat. However, the issue arises when we try to apply this concept to weight management.
The popular belief is that weight loss is simply a matter of eating fewer calories than you burn through exercise. This “calories in, calories out” method has been ingrained in our minds as the key to weight management. But according to Dr. Giles Yeo, this oversimplified approach doesn’t take into account the complex interplay of factors that actually influence our weight.
One of the main reasons why calorie counting isn’t effective is because not all calories are created equal. Our bodies process calories from different foods in different ways. For example, ultra-processed foods, which are high in sugar and unhealthy fats, can disrupt our body’s natural signals that regulate hunger and fullness. This can lead to increased cravings and overeating, making weight management a constant battle.
Additionally, genetics play a significant role in how our bodies store and burn calories. Some people may have a genetic predisposition to store more fat, making it harder for them to lose weight through traditional methods. Brain signals and gut health also influence our weight, as they can affect our appetite, metabolism, and digestion.
So, what’s the solution to sustainable weight management? Dr. Giles Yeo advocates for a more balanced, plant-rich diet that focuses on nutrient-dense foods. By prioritizing whole foods and minimizing ultra-processed foods, we can support our body’s natural mechanisms for weight regulation.
In conclusion, weight loss is not as simple as eating less and moving more. It’s about understanding the intricate relationship between genetics, brain signals, gut health, and food choices. By debunking the myth of calorie counting and embracing a holistic approach to weight management, we can achieve long-term health and wellness. And so hence this whole concept of calorie as a unit of heat has a rather interesting and somewhat bizarre history. The story of Wilbur Olin Atwater, a professor of biochemistry from Wesleyan University in the late 1800s, is a tale of dedication to understanding the nutritional content of food.
Atwater spent 20 years of his life burning food, feeding it to people, collecting their poop, and then burning that as well to figure out how much energy was being absorbed by the human body. His goal was not weight gain or weight loss, but rather to understand how much food people were actually absorbing.
Through his research, Atwater discovered that not all the food we eat is absorbed by the body. Some of it passes through and is excreted. This led him to develop general factors for calculating the amount of calories in different macronutrients – four calories for every gram of carbohydrate, four calories for every gram of protein, and nine calories for every gram of fat.
While Atwater’s work was not focused on weight gain specifically, his research laid the foundation for understanding the energy content of food and how it relates to human metabolism. Today, the calories listed on food packaging are based on Atwater’s calculations from his years of burning food and feces.
While Atwater’s methods may seem strange and somewhat Frankenstein-esque, his work was groundbreaking in the field of nutritional science. He provided valuable insights into the digestibility and energy content of different foods, helping to shape our understanding of nutrition and metabolism. And although his research may have involved some odd food choices (such as organ meats), it ultimately contributed to our knowledge of how the body processes and absorbs energy from the foods we eat. But they were whole foods because we were talking 1880, 1899, 1900’s. So it wasn’t what we would see typically today, if we, for example, went into a supermarket. That is not the kind of food that he necessarily would have been burning. They didn’t exist at the time.
Jonathan Wolf: That’s interesting. None of the ultra-processed foods or even processed foods that we might think about today. It was all raw ingredients that someone would cook up.
Giles Yeo: Absolutely.
Jonathan Wolf: That’s fascinating. So how do we jump from this story 120 years ago of, Oh, I’m curious about how much energy there is in food to how we think about calories today, where they are sort of like this secret of how you’re supposed to manage your weight in a world where it seems like we have to manage our weight because otherwise, we all put on weight.
Giles Yeo: So another brief history and then I promise I’ll stop with a history lesson. There was a doctor actually in just around the World War I period called Lulu Hunt Peters. And she was a woman doctor, a female doctor, which was unusual enough in the early 1900s, and she was by all accounts a larger lady, shall we say.
But because she was a doctor, she was a scientist, she then caught up and became acquainted with Atwater’s publications about these things. And she began to realize that, well, hang on a second, there must be some physics involved. Okay. I need to lose weight, I’m a larger lady.
So what she then began to do was to say, wow, instead of thinking about eating less food in order to lose weight, I am now going to put a number on it. I am going to quantify the food.
She then now takes Atwater’s lists, which were by all accounts, quite dry, aside from the fact that you can look at all these organ weights and things, but converted all of them into calories. So obviously she used imperial numbers, you know, what would be three ounces of bacon, for example, in terms of calories.
She then converted all of these lists into two, three, four ounces, whatever a serving size someone might have eaten in the early 1900s. And then converted those into calories.
All her writings and she became a syndicated columnist for the New York Times and what have you, so she put this into newspapers. Directed to ladies, she was targeting this to ladies.
And so she would say, ladies, what you need to do if you want to lose weight, is you need to eat three ounces of this and well, four ounces of that. Don’t think about a slice of pie. Don’t think about a rasher of bacon. Think about the number of calories of pie. Think of the number of calories of bacon.
Jonathan Wolf: So, Giles, she was like the original MyFitnessPal with her lists and her thing that, if you just count your calories and eat less, then you’re going to lose weight.
That’s where this all starts.
Giles Yeo: She also came up with her own version of the BMI, so it was a lot more complicated than the BMI, we can debate BMI later, but she then had some way of saying, well, what should your ideal weight be?
It was an early proto-BMI thing. So she was the first person to weaponize the calorie. In fact, I would argue that she is probably the mother of the diet industry. From there, she then converted all of these columns into a book. And then she published it.
Then in the meantime, she went to post World War one to the Crimea. She was a doctor. So she worked for the Red Cross for four years in the Balkans. And she came back and realized that in the intervening four years, her book, her calorie counting book had topped. The New York Times bestseller list, four years in a row.
Jonathan Wolf: So we’ve been obsessed about calorie counting for a really long time. I thought about that as a sort of 1960s onwards or something, but you’re actually saying that for a hundred years, we’ve been obsessed with the idea that if you count calories, that’s the secret to losing weight and looking better and all these other things.
Giles Yeo: And it is unusual to think about it because we think of obesity, overweight, metabolic diseases, what we’re talking about today as a relatively contemporary problem. Certainly, at least at the scale it is, and that is true to an extent.
But what this little vignette of a story tells us, this little history lesson tells us that, okay, she was a privileged lady, obviously, and the United States was not stuck in a war at the time, so there was a growing middle class, and there was a growing concern about looks, I would say, and weight gain between 1910 and 1920, calorie counting was born.
Jonathan Wolf: Giles, you said something that I want to pick up on. You said she weaponized the calorie, which is a very strong statement. Could you explain?
Giles Yeo: She formalized how to measure the energy and food for someone who was trying to lose weight.
When I mean weaponize, I mean she took the slightly esoteric science of Atwater, of calories, of macronutrients, of stuff, and then boiled it down into really actionable information that an averagely educated American woman in the early 1900s could say, okay, so I now need to eat this much less bacon, this much less eggs in order to do it. That’s what I mean by weaponized.
I think that the toxicity of the diet industry came a bit later when more and more people started jumping on the bandwagon and then all the food companies started jumping on. I think that’s a later thing.
But she definitely did action calories for food in terms of weight. She was definitely the first person that did that.
Jonathan Wolf: So lots of people will be listening to this and saying, what’s the problem here, Giles? Everybody knows that you need to count your calories. But the quality of those calories matters just as much as the quantity. Eating 300 calories of nutrient-dense, whole foods like vegetables, lean proteins, and whole grains will provide your body with the necessary nutrients it needs to function properly. On the other hand, consuming 300 calories of processed junk food will not only leave you feeling hungry and unsatisfied, but it will also lack the essential nutrients your body needs to thrive.
Additionally, focusing solely on calorie counting can lead to an unhealthy relationship with food. It can create a sense of restriction and deprivation, making it difficult to sustain in the long term. This can often lead to binge eating or other disordered eating behaviors.
Instead of obsessing over calorie counts, it’s important to focus on eating a balanced diet that includes a variety of whole foods. Listen to your body’s hunger and fullness cues, and eat mindfully. Pay attention to how different foods make you feel physically and emotionally, and make choices that support your overall health and well-being.
In conclusion, while calorie counting can be a useful tool for some people, it’s important to remember that it’s not the be-all and end-all when it comes to weight loss and overall health. It’s essential to consider the quality of the calories you’re consuming, as well as your overall relationship with food. By focusing on nourishing your body with nutrient-dense foods and listening to your body’s cues, you can achieve a healthy weight and improve your overall well-being without the need to constantly count calories. The debate over calorie counting and weight management is ongoing, with many experts weighing in on the topic. One such expert is Giles Yeo, who believes that focusing solely on calories is not the most effective way to approach weight loss. In a recent podcast interview, Yeo argued that the calorie is a “completely useless number” when it comes to determining the quality of our food.
Yeo pointed out that not all calories are created equal, and that our bodies extract differing amounts of energy from the foods we eat. For example, he mentioned sweetcorn, which our bodies do not absorb all of the calories from. This means that simply counting calories may not accurately reflect the true nutritional value of our food.
Instead of fixating on calorie counts, Yeo suggests focusing on the quality of our food. He emphasized the importance of eating less but eating better quality food. Yeo believes that the key to weight management lies in understanding the complex biological and psychological factors that influence our appetite and eating habits.
The conversation with Yeo shed light on the fact that weight management is not as simple as calories in versus energy out. Our bodies are complex systems that respond differently to food based on a variety of factors. Understanding these factors and making informed choices about the quality of our food may be a more effective approach to achieving and maintaining a healthy weight.
In conclusion, Giles Yeo’s perspective on calorie counting and weight management challenges the traditional notion that calories are the sole determinant of weight loss. By considering the quality of our food and addressing the underlying factors that influence our eating habits, we may be able to achieve better, more sustainable results in our weight management journey. And so I know that I do it and you try and organize your life so you don’t do it, but sometimes you just do it.
Having followed sort of my diet now for quite a few years is that it feels as though my appetite has changed a lot and that I don’t have the same level of, I don’t quite know how to even describe it, like sudden hunger bursts in the same way, but what’s going on there, Giles?
Giles Yeo: So appetite is an interesting term because we sort of understand it, we talk about appetite, but it’s actually quite a complex concept because it’s an integrated concept.
What do I mean by this? In my head, I simplify appetite into a triangle. Okay, of which there are three points.
One is hunger. So how hungry do you feel? I think we understand what that means. One is, how full are you? Now, that is not the same thing. How hungry you and how full you are, are different circuits within the brain. And the reward elements of food, how nice or lovely does the food taste to you? Okay, now those three all speak to each other. They’re not mutually exclusive and they involve different parts of the brain. And if you tug on one side of the triangle, the shape of the triangle changes. Correct. And so in other words, if you are more hungry, for example, you’re going to take more food to get filled up. And if you’re more hungry, the food has to be less rewarding for you to enjoy the food.
If you’re really, really, really starving, a bit of bread, a bit of cheese, a bit of rice, it’s like the simplest foods are the best. If you are not hungry, suddenly the rewarding element of the food has to be really, really big for you to continue eating. It is the concept of the dessert tummy, where why after a full meal, you’re never going to order another steak after a meal or whatever it is you’re eating, but chocolate comes and you eat it.
Jonathan Wolf: My son has explained that he’s got a separate ice cream stomach for the last decade.
Giles Yeo: Yes, and he’s right.
Jonathan Wolf: He’s right, is he? He thinks it’s in his legs, or at least when he was six he did. Where is his dessert stomach and how does that work?
Giles Yeo: So the dessert stomach is this integrated concept where the fuller you are, okay, the more rewarding the food has to be. So let me give you an example from an evolutionary perspective, okay. Take the grizzly bear, okay, Pacific Northwest, Oregon, Washington area, hitting the salmon run, preparing for hibernation.
Jonathan Wolf: And just to be clear, the salmon run isn’t like a running race or a ski race. The salmon run is…
Giles Yeo: Is when the salmon are swimming up the river in order to reach their spawning grounds and the grizzlies know this. And so they kind of park themselves in between the spawning ground and where the salmon are coming in and eat the salmon.
At the beginning of the salmon run, the bear eats the whole salmon, down to the bone. Okay? He just eats it, and you can see there’s just a whole pile of bones. But as the bear gets fuller and fuller and fatter and fatter because he’s trying to gain fat, the bear only eats the skin of the salmon and the fat underneath the skin of the salmon.
Why? Because this is calorically wise, even though they don’t count, it’s the densest part of the fish. And you can do this. This is what the bear does because he or she is trying to continue to stuff as many calories into his body as possible even when he’s now completely full.
Jonathan Wolf: So he’s eating the really fatty bits because that doesn’t take up as much space. It’s like bare chocolate.
Giles Yeo: It’s bear chocolate. Now, clearly, desserts are a human-specific cultural underpinning. So the bear is not having dessert, But this concept of which the fuller we become, the more dense the food we want to eat before we actually will bother doing it before it tickles the reward parts of it, is a conserved thing.
So your dessert tummy is not a human-specific thing. It is a conserved behavior. So it’s got to be high in energy density, okay? So in other words, for every given gram of food you eat, you get more, more energy in it. So what are those? Those are going to be foods that are high in sugar, free sugars, or high in fat. What are foods that are high in sugar and fat? They’re desserts.
So that, primarily, is the big driver. So fatty foods or sugary foods. 50,000 years ago on the Savannah, you know, no, we’re not going to be eating a tart au citron, and a muscat, but it might be honey. It could be a really ripe fruit, it could be making sure you eat the fat bit of your steak or bison or venison or whatever it is you’re actually eating.
Today it’s a tart au citron. But the whole thing is you’re looking for something high in fat and high in sugar so that you can continue stuffing food into all the nooks and crannies, even after you’ve eaten 2000 calories worth of venison. Because you have to remember that aside from the past 30 or 40 years of human history, most of the time we never had enough food, broadly speaking, okay? And so the primary driver, the existential driver, is to make sure you ate when the food was there.
We are designed for a feast-famine environment. That’s the natural way, sometimes there was antelope, sometimes there’s no, no antelope. Sometimes you found the turnip, other times you didn’t find the turnip. Even with agriculture, it was a scrabbling existence. Our drive to eat is a fundamental biological instinct that has been shaped by evolution to ensure our survival. In a feast-famine environment, our bodies are designed to store fat during times of plenty to prepare for times of scarcity. However, in today’s modern world of abundant food availability, this evolutionary mechanism can work against us.
When we start to lose weight, our brain interprets it as a threat to our survival and triggers mechanisms to increase our appetite and drive us to eat more. This response is subconscious and driven by a complex interplay of hormones and neural circuits in the brain.
The gut also plays a crucial role in regulating appetite. Different types of food trigger the release of different gut hormones that signal to the brain whether we are hungry or full. The composition of our gut microbiome, which is influenced by the foods we eat, can also impact our appetite and how our body responds to different types of food.
While calorie intake is still important, there is a growing emphasis on the quality of the food we eat and how it affects our appetite and overall health. Ensuring a diverse and fiber-rich diet can help maintain a healthy gut microbiome, which in turn can influence our appetite regulation and metabolic health.
Ultimately, understanding the complex interplay between our brain, gut, and microbiome can help us make more informed choices about the foods we eat and how they impact our hunger and satiety cues. By paying attention to these biological signals, we can better navigate the challenges of living in a feast-feast environment and support our overall health and well-being. And ultimately it does begin to change. It certainly influences hormonal release and therefore will impact your appetite if you don’t have a healthy microbiome.
Jonathan Wolf: So Giles, I’d love to switch gears to discuss what actions individuals can take. I can’t stop thinking about the bear story you mentioned earlier, just eating the fatty salmon and how that relates to my love for chocolate. This leads me to think about ultra-processed foods and our inability to resist them. How does this tie into appetite control, and what should we be cautious of?
Giles Yeo: When it comes to weight loss, the simplest way to achieve it is by eating less, but that’s easier said than done. The key to eating less is feeling fuller, and there are strategies we can implement to help with that. Foods that take longer to digest, such as protein, can make you feel fuller compared to fats and carbs. Additionally, foods high in fiber can also contribute to a feeling of fullness.
The issue with ultra-processed foods is that they are typically low in protein and fiber, while high in sugar, salt, and fat. This combination makes them easy to digest and lacking in satiety, leading to overeating. The flavor in these foods often comes from added sugar, salt, and fat, further driving appetite and consumption.
Jonathan Wolf: It seems like ultra-processed foods are not only less filling but also somehow manipulating our responses. Is there a connection between these foods and our innate food preferences?
Giles Yeo: Absolutely. Ultra-processed foods not only lack satiety but also have a unique effect on our brains. Studies have shown that when fat and carbs are combined, our brains light up in response to the reward of delicious food. This combination hijacks our brain’s systems and can lead to increased hunger and cravings.
In conclusion, being mindful of the types of foods we consume, opting for whole foods higher in protein and fiber, can help regulate appetite and promote weight loss. Avoiding ultra-processed foods that are high in sugar, salt, and fat can prevent overeating and support overall health. Remember, what we eat not only impacts our physical health but also influences our brain’s response to food cues.
By making informed choices and prioritizing nutrient-dense, whole foods, we can support our bodies and minds in achieving optimal health and well-being. The debate over ultra-processed foods and their impact on our health is a complex and ongoing one. In a recent podcast, Giles Yeo delved into the evolutionary reasons behind why our brains respond so strongly to foods that are high in both fat and carbs, like pizza. He explained that this combination is rare in nature, with milk being one of the few examples, and hypothesized that our brains are wired to seek out foods with this mix in order to ensure rapid growth and survival, as milk is a prime source of nutrition for baby mammals.
Yeo also discussed the concept of ultra-processed foods and the need for a more nuanced approach to categorizing them. While some foods clearly fall into this category, such as heavily processed snacks and sugary beverages, others, like natural yogurt with added fruit, may not necessarily be as harmful. He emphasized the importance of not demonizing all processed foods and instead focusing on reducing consumption of the most heavily processed and unhealthy options.
However, Yeo also acknowledged the challenge of making healthier foods more affordable and accessible to all, as ultra-processed foods are often cheaper and more readily available. He called for a balanced and equitable approach to improving the food environment, one that does not stigmatize those who may not have the means to purchase healthier options.
Overall, Yeo’s insights shed light on the complexities of the modern food landscape and the need for a more nuanced understanding of the role of ultra-processed foods in our diets. By engaging in thoughtful and informed discussions, we can work towards creating a healthier and more sustainable food environment for all. And one of the things, one of the reasons we do this podcast among other things is that we believe a lot of that starts with demand. I think it’s not as true really that it’s not possible to make food that is whole and healthy at prices that can work. Giles Yeo: I agree with you. Jonathan Wolf: But if there’s no demand for it, then it doesn’t matter. So hopefully some people are listening to this and it will have some impact on how they think about what they should do. We talk about this mix between weight loss and weight management.
I think there’s a lot of people who like me suddenly realize, well, I’ve got to make a change or otherwise I’m going to just keep putting on this weight. I have found in fact, since I met Tim, interestingly, my weight has been really stable for the last eight, seven years, I guess, without worrying about it.
Is there any other actionable advice you’d want to give for people who are looking to, you know, lose weight or maintain weight better, other than that?
Giles Yeo: I think there are three numbers that I would think that people think about. The first is 16, okay? And this is the percentage in terms of the energy of protein that you should be consuming. And there is a sweet spot for the amount of protein to eat, unless you’re an Olympian or unless you are ill and in ITU. If you’re a relatively healthy human being here, you should be aiming for 16 % of protein in your diet. Too much, your liver and kidneys begin to stress out. Too little, you don’t get enough.
And I’m not only talking steak, just to be clear. Tofu, beans, any source of protein, vegetables, or animals will work. So 16. 30, the next number. This is the grams of fiber we should be aiming to consume in our diet. At the moment, on average, in this country, in the United States, we’re looking at maybe only 15, at a stretch, 20 grams of fiber a day.
We need to double the amount of fiber we’re eating. Fiber only comes from plants and from fruits. So I mean, eat more fruits and vegetables. And the third number is five. And this is the percent that we’ve got to keep under, of the free sugars in our diet. So free sugars are sugars that are not tied up in fiber. Eat as much fruit as you want, please, because it’s tied up in the fiber. I’m talking about anything that’s been extracted. So yes, the white powdered stuff, honey, Agave nectar, maple syrup, and yes, they’re all the same thing, even though they taste differently. Okay, we want to keep this added sugar to 5% or less.
So to my mind, those are the three numbers to think about. 16% for protein, 30 grams for fiber, and 5% or less for free sugars. Apply that to whatever dietary approach, whatever church you worship of the dietary gods. And I think that’s going to be good for you.
Can I try and do a quick summary of what I heard and then you correct me when I get it wrong?
Giles Yeo: Okay. Let’s do that. Jonathan Wolf: We started by basically explaining calorie counting doesn’t work. And you described this wonderful lady, was it Lulu Hunt Peters, I will be googling her after this, who basically created the first ever MyFitnessPal. Had a four-year New York Times bestseller and basically invented this idea that here are all the calories and you should count them and if you reduce them, you know, that’s the secret to losing weight.
And basically, we’ve been talking about this for a hundred years, but it doesn’t work. And what you said is the easiest way to lose weight is to feel fuller, right? So the reverse of counting calories, forget about that, how can you feel fuller? And what that means is you need to change the sort of food that you’re eating. And what it also means is it switches this focus suddenly to the brain.
What you’re saying also is that you and your colleagues have literally been imaging these brains and seeing what’s going on. Appetite is this real thing in your brain. You are figuring out the particular circuits of how this works and it’s very complicated because you talked about how there’s hunger but also how full you are but also how like delicious it is.
Basically, the food that we’re eating now is sort of messing with all of this over time and causing these problems. And I know we didn’t really get into these new drugs like Ozempic, but you can see how, over time, this leads us to the point that the brain is so damaged that you end with this.
But interestingly, I think I took away two things. The first is my dessert tummy and my son’s dessert tummy is real, but it only works for particular sorts of food. And this is not something we’ve invented in the last hundred years. You were giving this brilliant example of bears, they have the dessert tummy as well, but it works for particular sorts of food. And the reason why I crave chocolate, I guess at the end of the evening is it’s one of those foods which has got sugar and fat.
You said to me the only thing in real life that has that was my mother’s milk. So I’m like built to like that from a small child. But all of this modern ultra-processed food triggers this and so you’re saying my brain goes off like a Christmas tree when I see it and it’s not supposed to happen and so this explains why. It’s not your fault you want this stuff, right? This stuff has been built to overcome your natural desire.
Then I think the other thing you talked about is that the gut hormones have this huge impact on how hungry you feel. The importance of gut health and its impact on our overall well-being cannot be overstated. In a recent interview with Giles Yeo, a renowned expert in the field of nutrition, the conversation delved into the connection between what we eat and how it affects our gut microbiome.
Yeo highlighted the significance of consuming foods rich in fiber, which support the growth of beneficial bacteria in our gut. These bacteria play a crucial role in producing gut hormones that regulate hunger and satiety. Without a diverse and healthy microbiome, we may be missing out on essential signals that tell us when we’re full or hungry.
Furthermore, Yeo discussed the psychological aspect of weight loss and how our brains are wired to resist shedding pounds due to a primal fear of starvation. This innate survival mechanism can sabotage our efforts to lose weight, making it challenging to maintain a healthy diet and lifestyle.
The traditional notion of weight management, based solely on calories in versus calories out, is outdated and oversimplified. The complex interplay between our gut health, hormones, and brain chemistry underscores the need for a more holistic approach to nutrition and wellness.
In conclusion, Yeo’s insights shed light on the intricate relationship between our gut and overall health. By prioritizing foods that nourish our microbiome and understanding the psychological barriers to weight loss, we can take proactive steps towards improving our well-being. It’s time to embrace a new paradigm of nutrition that goes beyond calorie counting and focuses on nurturing our gut health for long-term vitality.