The question of weight loss is omnipresent in public debate, where it is often reduced to a question of personal will. But after about fifteen years of research in health and nutrition, I found that the weight problem was not housed in the same brand as the majority of other health issues. People are regularly responsible for their weight, while tangible elements show that it results from a complex combination of genetic, biological, environmental and socio-economic factors.
Access limited to healthy and affordable foods, the lack of possibilities of doing physical exercise, including a lack of appropriate places, extended working days and chronic stress – more frequent, in disadvantaged areas – can considerably complicate the maintenance of a shape. Here are five things I would like more people understand about weight loss.
1. It goes against our biology
Obesity has been recognized as a national health priority in England since the 1990s and many policies have been put in place to remedy it. However, obesity rates have not decreased – in France, the prevalence of excess weight (therefore including overweight and obesity) in 2020 was 47.3%, including 17% of subjects in obesity. This suggests that current approaches, which tend to focus on individual responsibility, do not work.
Even when the losing weight methods are effective, the results are often not durable. Studies show that most people who lose weight end up resuming and that the chances of an obese person to reach and maintain a “normal” weight are very low.
Body weight is determined by a multitude of factors. Genetics plays a major role, as well as environmental and social factors.
This is partly explained by the fact that our body reacts in its own way when we lose weight, by virtue of a biological mechanism anchored in our evolutionary past: it rebiffe. This process is called “metabolic adaptation”: when we reduce our calorie intake and lose weight, our metabolism adjusts its energy expenditure. The hormones of hunger – like the Ghrelin – an increase, which encourages us to eat more and to resume the lost weight.
This biological response had all its meaning in our past as hunter-gatherers, marked by an alternation of periods of abundance and famine. But today, in a world where ultra -formed and calorie foods are cheap and accessible, these same mechanisms promote weight gain and prevent losing weight. If you have trouble losing weight or maintaining it, it is not a personal failure, but a predictable physiological response.
2. It is not a question of will
Some people manage to maintain their weight with relative ease, while others have trouble. The difference is not only a question of will.
Body weight is determined by a multitude of factors. Genetics plays a major role, for example by influencing the speed at which we burn calories, our feeling of hunger or our feeling of satiety after eating. Some people are genetically predisposed to be hungry or want to energy rich in energy, which makes weight loss even more difficult.
Environmental and social factors also play a role. Have enough time and financial means to prepare balanced meals, practice regular physical activity, sleep well: all of this makes a real difference. However, these resources are not accessible to everyone.
By ignoring these complex factors and considering weight only as a question of will, stigmatization is supplied. Yet this can lead people to feel judged, ashamed or excluded, which, paradoxically, increases stress, decreases self-esteem and further complicates the adoption of healthy habits.
3. Calories do not do everything
Counting calories is often the default strategy to lose weight. And if creating a calorie deficit is theoretically essential to lose weight, in practice, it is much more complicated.
To begin with, nutritional information on food is only estimates and our energy needs vary from day to day. Even the amount of energy that we absorb from food can vary depending on how they are cooked, digested and the composition of our intestinal bacteria.
There is also a tenacious idea that “a calorie is a calorie”, but our body does not treat all calories in the same way. A cookie and a shell can contain an equivalent number of calories, but they have very different effects on our hunger, our digestion and our energy level. A cookie can cause a rapid increase in blood sugar levels, followed by a brutal fall, while an egg provides a more durable satiety (satisfaction) and a higher nutritional value.
False ideas have contributed to the popularity of fashionable regimes, such as diets based on shakes (protein drinks) or those that completely eliminate certain food groups. Although they can cause short -term weight loss by creating a calorie deficit, these diets are rarely durable and often have essential nutrient deficiencies.
A more realistic and balanced approach consists in focusing on long-term changes: eating more complete foods, reducing take-out meals, reducing alcohol consumption and adopting habits favorable to general well-being.
4. Physical exercise is excellent for health, but not necessarily to lose weight
Many people think that the more they exercise, the more weight they lose. But science shows us that reality is more complex. Our body is very good at keeping its energy. After an intense sporting session, we can unconsciously move less during the rest of the day, or be hungry and eat more, which compensates for the calories burned.
In fact, research shows that total daily energy expenditure does not increase with the increase in physical activity. On the contrary, the body adapts by becoming more effective and by reducing its energy consumption elsewhere, which makes weight loss by the sole bias of the exercise more difficult than many do not think so.
That said, physical exercise still offers a multitude of advantages: it improves cardiovascular health, mental well-being, maintains muscle mass, strengthens metabolism, consolidates bones and reduces the risk of chronic diseases. Even if the number on the scale does not decrease, physical activity remains one of the most powerful tools to improve our health and our quality of life.
5. Health improvement does not always go through weight loss
There is no need to lose weight to be healthier. If voluntary weight loss can reduce the risk of diseases, such as heart disease and certain cancers, studies also show that better quality food and moving more can improve health indicators, such as cholesterol, blood pressure, blood sugar and insulin sensitivity, even if your weight remains the same.
If the balance does not reflect a significant change, it may be preferable to adopt another approach. Rather than focusing on a figure, you can choose a more global approach: suitable diet, regular and pleasant physical activity, attention to sleep quality and better stress management. Weight is just a piece of the puzzle and health is much more than that.
