Effects of a high protein very-low-energy diet on ambulatory subjects with special reference to nitrogen balance.

Forty young healthy ambulatory volunteers were given a very-low-energy diet (2.34 MJ, 560 kcal) containing 70 g of proteins of good biological value, 36 g carbohydrates, 2 g potassium, 0.5 g sodium, polyvitamins and 21 water. The nitrogen balance reached equilibrium on the 8th day. No risk factors were found. These results were compared with 4000 cases collected over 12 years. The latter were given a protein diet with neither salt nor carbohydrates. The addition of salts and carbohydrates resulted only in an increase of the subjects' comfort. The analysis of deaths occurring in the U.S.A. after protein diets lead to the conclusion that these very probably linked to the duration of the protein diet, the poor biological value of proteins provided, the insufficiency in potassium intake. The conditions for a safe use of a very-low-energy diet, are a large intake of proteins of good biological value, a large intake of potassium and probably small intake of carbohydrates and sodium.