Obesity is a major public health problem in France, as in most industrialised countries. Indeed, in addition to the excessive development of adipose tissue which characterises obesity, it represents a major risk factor in the development of numerous pathologies (cardiovascular diseases, type 2 diabetes, hepatic steatosis, etc.), thus increasing the risk of morbidity and mortality in industrialised countries.
In addition to the quantity of lipids ingested and the caloric value of the diet, the nature of the fatty acids consumed is a major factor in the development or prevention of obesity.
Thus, saturated fatty acids are considered to have an "obesogenic" effect, whereas polyunsaturated fatty acids (n-3 PUFAs), in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), could help prevent obesity. Few studies have examined the specific effects of their metabolic precursor: alpha-linolenic acid (ALA).
In this context, the Nutrition, Metabolism and Health Team at ITERG has conducted a study on animal models to define the optimal level of ALA intake and the optimal omega-6 to omega-3 ratio to be used to prevent the metabolic consequences of a hyperlipidic diet, which induces obesity.

The data acquired during this project show that the substitution of a part of the SFAs in a hyperlipidic diet by ALA makes it possible to limit the development of adipose mass and to regulate plasma triglyceridemia to values comparable to those of animals subjected to a balanced normolipid diet. In addition, diets rich in ALA help to prevent the accumulation of lipids in the liver, which is the cause of the many metabolic disorders (inflammation, insulin resistance, etc.) associated with obesity.

The overall results of this project suggest a preventive effect of ALA in the development of obesity, demonstrating the potential benefit of a qualitative rebalancing of the fatty acids consumed, in favour of omega-3 of plant origin.

Contact: Carole Vaysse, Head of Health Nutrition and Lipid Biochemistry Unit, ITERG.