The effect of a low-fat, high-protein or high-carbohydrate ad libitum diet on weight loss maintenance and metabolic risk factors

Int J Obes (Lond). 2009 Mar;33(3):296-304. doi: 10.1038/ijo.2008.278. Epub 2009 Jan 20.

Abstract

Background: High-protein (HP) diets are often advocated for weight reduction and weight loss maintenance.

Objective: The aim was to compare the effect of low-fat, high-carbohydrate (HC) and low-fat, HP ad libitum diets on weight maintenance after weight loss induced by a very low-calorie diet, and on metabolic and cardiovascular risk factors in healthy obese subjects.

Design: Forty-eight subjects completed the study that consisted of an energy restriction period of 5-6 weeks followed by a weight maintenance period of 12 weeks. During weight maintenance subjects received maltodextrin (HC group) or protein (HP group) (casein (HPC subgroup) or whey (HPW subgroup)) supplements (2 x 25 g per day), respectively and consumed a low-fat diet.

Results: Subjects in the HP diet group showed significantly better weight maintenance after weight loss (2.3 kg difference, P=0.04) and fat mass reduction (2.2 kg difference, P=0.02) than subjects in the HC group. Triglyceride (0.6 mM difference, P=0.01) and glucagon (9.6 pg ml(-1) difference, P=0.02) concentrations increased more in the HC diet group, while glucose (0.3 mM difference, P=0.02) concentration increased more in the HP diet group. Changes in total cholesterol, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, insulin, HOMAir index, HbA1c, leptin and adiponectin concentrations did not differ between the diets. No differences were found between the casein- or whey-supplemented HP groups.

Conclusions: These results show that low-fat, high-casein or whey protein weight maintenance diets are more effective for weight control than low-fat, HC diets and do not adversely affect metabolic and cardiovascular risk factors in weight-reduced moderately obese subjects without metabolic or cardiovascular complications.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Biomarkers / blood
  • Blood Glucose / metabolism
  • Cardiovascular Diseases / prevention & control
  • Diabetic Angiopathies / blood
  • Diabetic Angiopathies / diet therapy*
  • Diabetic Angiopathies / prevention & control
  • Diet, Fat-Restricted / adverse effects
  • Diet, Reducing* / adverse effects
  • Dietary Carbohydrates / administration & dosage
  • Dietary Carbohydrates / adverse effects
  • Dietary Proteins / administration & dosage
  • Dietary Proteins / adverse effects
  • Female
  • Humans
  • Male
  • Metabolic Syndrome / prevention & control
  • Middle Aged
  • Obesity / blood
  • Obesity / complications
  • Obesity / diet therapy*
  • Polysaccharides / administration & dosage
  • Polysaccharides / adverse effects
  • Risk Factors
  • Triglycerides / blood
  • Weight Loss / physiology

Substances

  • Biomarkers
  • Blood Glucose
  • Dietary Carbohydrates
  • Dietary Proteins
  • Polysaccharides
  • Triglycerides
  • maltodextrin