title: Normal vs. high-protein weight loss diets in men: effects on body composition and indices of metabolic syndrome.
abstract: OBJECTIVE
  This study assessed the effectiveness of a prescribed weight-loss diet with 0.8 versus 1.4 g protein·kg(-1) day(-1) on changes in weight, body composition, indices of metabolic syndrome, and resting energy expenditure (REE) in overweight and obese men.
  
  
  METHODS
  Men were randomized to groups that consumed diets containing 750 kcal day(-1) less than daily energy needs for weight maintenance with either normal protein (NP, n = 21) or higher protein (HP, n = 22) content for 12 weeks. The macronutrient distributions of the NP and HP diets were 25:60:15, and 25:50:25 percent energy from fat, carbohydrate, and protein, respectively. Assessments were made pre and post intervention. The subjects were retrospectively subgrouped into overweight and obese groups.
  
  
  CONCLUSIONS
  Both diet groups lost comparable body weight and fat. The HP group lost less lean body mass than the NP group (-1.9 ± 0.3 vs. -3.0 ± 0.4 kg). The effects of protein and BMI status on lean body mass loss were additive. The reductions in total cholesterol, HDL-C, triacylglycerol, glucose, and insulin, along with LDL-C, total cholesterol-to-HDL-C ratio, and HOMA-IR, were not statistically different between NP and HP. Likewise, macronutrient distributions of the diet did not affect the reductions in REE, and blood pressure. In conclusion, energy restriction effectively improves multiple clinical indicators of cardiovascular health and glucose control, and consumption of a higher-protein diet and accomplishing weight loss when overweight versus obese help men preserve lean body mass over a short period of time.
authors.affiliation: Department of Nutrition Science, Purdue University, West Lafayette, Indiana, USA.
authors.forename: Minghua
authors.initials: M
authors.lastname: Tang
authors.forename: Cheryl L H
authors.initials: CL
authors.lastname: Armstrong
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Leidy
authors.forename: Wayne W
authors.initials: WW
authors.lastname: Campbell
mesh_terms: D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis; D001823:Body Composition; D015992:Body Mass Index; D001835:Body Weight; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004038:Diet, Reducing; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage*; D002149:Energy Intake; D004734:Energy Metabolism; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000517:prevention & control*; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000178:diet therapy*; D012189:Retrospective Studies; D016896:Treatment Outcome; D014280:Triglycerides / Q000097:blood; D015431:Weight Loss; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D014280:Triglycerides