It is not the biological consequences of being overweight that lead to an increased risk of depression in obese people, but to its psychological impact, according to a study by Danish researchers.
Ten kilograms of excess fat leads to an increased risk of depression of 17%. This conclusion from a study conducted by researchers at Aarhus University Hospital in Denmark confirms the psychological link with an increased risk of depression for people suffering from obesity. But is this link exclusively psychological or can it be linked to biological parameters specific to the obese?
It is exclusively psychological, answers the Danish study published in the journal Translational Psychiatry which, because it identifies well as the cause of this risk the "bad overweight" by reconsidering the importance of the BMI (index of body mass), brings a new perspective on the definition and management of obesity when we consider that 40% of the adult world population is now overweight.
"The BMI of many athletes should classify them as overweight!"
Previous studies on the relationship between overweight and depression have used BMI to measure obesity. But this index is calculated solely on the basis of weight and size: it does not take into account the difference between muscle mass and body fat. "Many top athletes with high muscle mass and low fat will have a BMI greater than 25, which, according to the common definition, should classify them as overweight!", Explains Dr. Ostergaard, author of the study.
Scientists have therefore focused on measuring the link between the risk of depression and not overweight as it is commonly defined, but the fat mass. And this measure showed that people with a fat mass in the center of the body, the one with the highest biological risk, did not present more risk of depression. Conclusion: the link between obesity and risk of depression is exclusively psychological, related to self-image!
"Avoid doing more harm than good in the fight against obesity"
The team of researchers draws two important lessons from the results of this study. The first is that the psychological component of obesity should be treated as well as its physical consequences such as diabetes or cardiovascular disease. The second is that people suffering from obesity should not be stigmatized, including through campaigns intended to fight this disease. "Since the psychological consequences of obesity, such as a degraded body image or a weak self-esteem, is the main factor increasing the risk of depression, we must avoid doing more harm than good in the fight against the epidemic of obesity, "says Dr. Ostegaard.