Consequences of modified fasting in obese pediatric and adolescent patients. I. Protein-sparing modified fast.

Sixteen obese patients 9 to 16 years of age were treated with a protein-sparing modified fast for four weeks in a metabolic unit, using lean meat as the sole calorie-containing nutrient. Total weight loss was 7.11 +/- 0.33 kg (mean +/- SEM). One-half of the patients achieved positive daily nitrogen balance by the fourth week. Cumulative N balance was -28.8 +/- 10.0 gm. Serum albumin concentration remained normal. Hemoglobin and hematocrit values were stable, but decreases in total lymphocyte (P less than 0.005) and neutrophil counts (P less than 0.01) were noted. Cell-mediated immunity (four patients) remained normal. Protein synthetic and catabolic rates (two patients) revealed only minimal changes. Cumulative N balance correlated (P less than 0.01) with mean fasting serum insulin concentration, which was related (P less than 0.005) to body fat mass. The PSMF has therapeutic potential for achieving safe, rapid weight loss in severely obese older children and adolescents.