Protein requirements with very low calorie diets.

The goal of the dietary treatment of obesity is to reduce the patient's weight with minimum risk. This is accomplished by a dietary regimen which allows a preferential loss of body fat with a preservation of lean body mass. Total fasting leads to a loss of 150 grams of nitrogen in the first month alone. In a study by Hoffer et al. reported below, two levels of dietary protein were compared for their effects on nitrogen balance in 17 obese women on a low calorie (500 cal) weight reduction diet. After three weeks of adaptation to the diets, the group given 0.8 grams protein/kg were in -2 grams nitrogen balance while the group given 1.5 grams protein/kg were at zero nitrogen balance. It was concluded that protein intakes at the level of the recommended dietary allowance (0.8 g/kg) are not compatible with nitrogen equilibrium when the energy intake is severely restricted. While weight loss is the obvious goal for obese persons, a careful examination of the composition of the weight loss (protein, fat, water) is essential in defining the optimal dietary regimen.