Especially in January, we pay attention to what we eat. With the holidays we put on weight, and in January we try to shed the kilos again. However, we don’t need to constantly track calories, says obesity researcher Giles Yeo. He wrote the book Why calories don’t count.
The Atkins Diet, the Paleo Diet, the Keto Diet, the Carnivore Diet (yes, they exist) – thousands of diet books tell us what to eat. British neuroendocrinologist Giles Yeo has his reservations about all this good but stern advice. In his book Why calories don’t count he describes what we know about how our body handles food and makes simple recommendations. Perhaps his most important conclusion: instead of spending our lives obsessing over our weight and how we look, we should pay more attention to our health.
In the 19th century, nutritionists viewed man as a small oven that burns food. They measured the energy content of fat, protein and carbohydrates in bomb calorimeters, and it is the number of calories that we still find in small print on the side of food packaging. But, says Yeo, the amount of calories listed on the package does not equal the number of calories in the food, nor does it equal the number of usable calories we get from the food.
Dossier: Know what, how, why and for what you eat During the holidays we often eat and drink a little more than is necessary or sensible. Immediately after that comes the period when we make our good intentions…
In his book, Yeo describes how we came to our current understanding of food and what our bodies do with all those calories, or what they do to our bodies. Gradually, as the necessary biochemistry and physiology pass in the revision, it turns out that reality is much more nuanced than just protein, fat and carbohydrates.
Yeo herself investigates how people handle food in their own way due to genetic differences. “Body weight is not a choice,” he writes, and there is no magic solution that will make everyone lose weight.
Any diet that helps you lose weight works, and many diets don’t work because we can’t possibly sustain them. However, there are the necessary diets with a pseudoscientific basis. Yeo: ‘Any diet that restricts food intake and therefore weight will work. But some diets work for different reasons than diets influencers to claim. If something goes wrong, it’s hard to repair the damage.’
Risks include, for example, that certain vitamins are lacking in the diet or that the diet is too one-sided. And a diet isn’t always necessary, even though our society tends to be quick to judge if someone is fat. We don’t yet know when someone has too much fat: it varies from person to person. Only when obesity causes complaints do we notice that someone has crossed a line.
Two topics are covered in detail in the book, and they are fiber and ultra-processed foods.
Fiber is good for bowel function. Intestinal bacteria can release nutrients from it. More importantly, fiber lowers the caloric availability of our food – it slows down the rise in blood sugar. Therefore, according to Yeo, eating an orange (with fiber) is better than drinking orange juice (without fiber).
Ultra-processed food is an achievement of modern society. There are plenty on the shelves in the supermarket. Where processed foods are, for example, canned vegetables and dried sausages, ultra-processed foods include soda, chips, ice cream, frozen pizzas, hamburgers, frikandelle, desserts… Delicious and above all unbalanced. It’s easy to eat too much of it, it’s cheap and it doesn’t require much cooking knowledge.
Yeo sees that healthy food today is a privilege, and there is a socio-economic component to the consumption of ultra-processed food with its associated negative health effects.
When asked, he says it would be good if snack bars selling lots of ultra-processed food were not located near schools and that fast food advertising aimed at children was limited. “But it’s even better,” he qualifies, “when fast food manufacturers incorporate more protein and fiber into their products. If you add soluble and insoluble fiber to ultra-processed food, it may not be healthier than an apple, but if you want a chocolate bar, I think you can choose a healthier chocolate bar.’
That cover is not easy. Yeo: ‘Some restaurants serve brown rice and whole wheat pasta, but the acceptance has cultural differences. I am of Chinese descent and am used to white rice and yellow noodles. The other texture and flavor is, despite what I know and study, not a suitable alternative!’
Yeo himself has now instituted a few meatless days and lunches each week. After an experiment where he only ate plant-based food, he has now become a flexitarian. He has noticed that he can keep the weight well with this.
With a little common sense, and possibly reading the packaging, we can adjust our diet without having to follow a strict diet. Yeo really thinks we should eat less meat and more plants. It is good for both our health and the environment.
He recommends more than 30 grams of fiber a day (a few slices of bread is 5 grams, and 100 grams of peas is 4.5 grams). The ideal amount of protein in our food is 16 percent of our daily energy needs. And free sugars, such as granulated sugar, high fructose corn syrup and the sugar in fruit juice, should be less than 5 percent of your daily energy needs.
In short, those looking to improve their lives in the guilt-ridden January after the high-calorie party month will take advice from Yeo: ‘Eat a little more protein, a lot more fiber and a little sugar! You can use these three rules in any of your favorite diets.”
Giles Yeo studied molecular cell biology at the University of California at Berkeley and received his Ph.D. from the University of Cambridge. Since August 2022, he has been professor of molecular endocrinology at the Medical Research Council in the Department of Metabolic Diseases. He is Honorary President of the British Dietetic Association.