(Montreal) We would benefit from betting on an improvement in lifestyle in the fight against obesity, rather than trying at all costs to achieve weight loss, experts argued Thursday, at the 89th congress of the French-Canadian Association for the Advancement of Science (Acfas).
The weight lost, for example through slimming diets, can be quickly regained, it was recalled. These diets may even have a deleterious impact on the health of those who adopt them, and who after several cycles of weight gain and loss will possibly end up with a higher weight than at the start.
“We know that it may not have very interesting effects either on mental health, on our self-esteem, then on the relationship we have with food or with our body,” added the professor. Benoit Arsenault, from the Interdisciplinary Research Group on Obesity at Université Laval.
The American Heart Association also recalled last year that studies have shown that weight loss is not accompanied by a reduction in the rate of cardiovascular disease.
On the other hand, a non-weight-focused approach that aims to improve factors such as diet and physical activity may be more promising for the patient’s health, argued the speakers.
To this end, it could be relevant to redefine what constitutes a “healthy diet”, underlined researcher Simone Lemieux of the NUTRISS Center at Laval University, since it is currently a somewhat abstract concept. which many associate with “restriction” and “moderation”.
You have to be careful when talking about healthy eating to avoid perpetuating the idea that eating healthy is only for weight loss, she said.
“There can be a kind of overlap between how eating is defined and being on a diet because there’s like an intersection between the two,” Lemieux explained. A lot of times people […] maybe feel a bit like they’re on a diet because they kind of feel like they’re restricting themselves in some of their food choices. »
Not everything that causes weight loss is necessarily healthy, she added, in the same way that everything that is healthy will necessarily prevent weight gain.
Multiple studies have shown a close association between increased physical activity and a reduced risk of cardiovascular events, even in people who are overweight.
“People are being told to find a way to improve their nutritional quality, to increase their level of physical activity, to find a sustainable way to do that too,” Professor Arsenault said.
Maybe the weight will go down, he continues, maybe it’ll stay the same, maybe it’ll go up in those who do a lot of resistance training, “but what we know is that this approach will have effects on cardiometabolic health, on mental health, on the relationship we have with food, with our body and on our self-esteem.
Obesity is a complex issue that cannot be reduced to a simple imbalance between the calories consumed and the calories expended. The roles played by environment and genetics, and often the intersection between the two, are becoming increasingly evident.
The higher the body mass index, the greater the influence of family history. It is estimated that in the case of an excessively obese patient with a BMI of 40 or greater, approximately 80% of body weight is an “heritable trait”.
“It’s pretty easy to say that genetic factors don’t have a relationship with weight when you’re thin to begin with,” Arsenault dropped.
Changes in our environment, such as the instant availability of ultra-processed foods, also have something to do with it.
A Norwegian study published in 2019 showed that people who had a genetic predisposition to be thin in 1966-1969 were still thin in 2017-2019. On the other hand, among individuals who had a genetic predisposition to be overweight, the prevalence of obesity was much higher.
“(It) shows that it’s the changes in our environment that are causing the prevalence of obesity to be much higher today than it was,” Arsenault said.