Optimal dietary therapy for obese adolescents: Comparison of protein plus glucose and protein plus fat

The observation of prolonged nitrogen losses in one subject on P + G and the limited experience with highly restrictive diets in obese adolescents emphasize that such diets must be used with caution and monitored carefully.

Abstract

Nitrogen balance in six obese adolescent boys and three obese girls was studied during two nonconsecutive three-week dietary periods. Protein intake was based on an ideal body weight calculated from the measurement of total body water. The diets consisted of 1.5 gm meat protein/kg IBW/day plus 1.0 gm glucose/kg IBW/day, or an isonitrogenous diet made isocaloric with fat. Each dietary period was preceded by a controlled five-day diet designed to achieve weight maintenance. The first dietary period was followed by a one-month period of re-equilibration. The addition of carbohydrate to protein produced a significantly better cumulative nitrogen balance than P + F. Significant nitrogen losses persisted throughout the entire dietary period of P + F in three patients, but were observed in only one patient during P + G. Lymphopenia occurred in one subject on P + F but did not occur during P + G. Serum albumin concentrations were unchanged on both diets. Transferrin values decreased during P + F, but did not differ significantly from prediet levels during P + G. However, the observation of prolonged nitrogen losses in one subject on P + G and the limited experience with highly restrictive diets in obese adolescents emphasize that such diets must be used with caution and monitored carefully.