Source: Dermatology  |  Posted 10 years ago

High-protein, low-fat diets are more efficacious for weight loss than high-carbohydrate, low-fat diets.

The result could be explained by the added energy-cost associated with the former, say researchers at Arizona State University East, United States, who compared both diets for the acute, energy-cost of meal-induced thermogenesis.

Ten campus female students, aged 19-22 years, took part in the randomised, cross-over designed study. These healthy, non-smoking volunteers consumed the high-protein and the high-carbohydrate diets for one day each.

Testing was separated by a 28 or 56 day interval. Control diets were consumed for two days before each test day when resting energy expenditure, non-protein respiratory quotient and body temperature were measured. Urine and fasting blood samples were collected.

Measurements taken after a 10 hour fast and at 2.5-hour post breakfast, lunch and dinner showed that postprandial thermogenesis averaged about twofold higher on the high-protein against the high-carbohydrate diet.

After breakfast and dinner the differences were significant (p<0.05) and after the dinner meal body temperature was slightly higher on the high protein diet (p=0.08). There was no difference between diets in changes in the respiratory quotient post meals and none in 24 hour glomerular filtration rates.

Nitrogen balance on the high protein diet was found to be significantly greater than the high-carbohydrate diet (7.6