Nutrient balance and body composition.

The prevalence of obesity in industrialized countries is increasing in spite of decreased energy and fat intakes. This trend might be mainly a consequence of a decline in energy expenditure. It is suggested here that it might also be accounted for by the increasing proportion of protein in the diet, affecting the hormonal status. The nutrient imbalance is particularly apparent in early childhood, when a low fat and high protein diet is not justified because of high energy needs for growth and because it is the period of high rate of myelinization of the nervous system. At later ages, the proportion of fat exceeds the recommended level, and the protein intake remains high. A diet containing less animal and more vegetable products would reduce both protein and saturated fat excesses and could help decrease metabolic risk factors.