title: The effects of low-carbohydrate versus conventional weight loss diets in severely obese adults: one-year follow-up of a randomized trial.
abstract: BACKGROUND
  A previous paper reported the 6-month comparison of weight loss and metabolic changes in obese adults randomly assigned to either a low-carbohydrate diet or a conventional weight loss diet.
  
  
  OBJECTIVE
  To review the 1-year outcomes between these diets.
  
  
  METHODS
  Randomized trial.
  
  
  METHODS
  Philadelphia Veterans Affairs Medical Center.
  
  
  METHODS
  132 obese adults with a body mass index of 35 kg/m2 or greater; 83% had diabetes or the metabolic syndrome.
  
  
  METHODS
  Participants received counseling to either restrict carbohydrate intake to <30 g per day (low-carbohydrate diet) or to restrict caloric intake by 500 calories per day with <30% of calories from fat (conventional diet).
  
  
  METHODS
  Changes in weight, lipid levels, glycemic control, and insulin sensitivity.
  
  
  RESULTS
  By 1 year, mean (+/-SD) weight change for persons on the low-carbohydrate diet was -5.1 +/- 8.7 kg compared with -3.1 +/- 8.4 kg for persons on the conventional diet. Differences between groups were not significant (-1.9 kg [95% CI, -4.9 to 1.0 kg]; P = 0.20). For persons on the low-carbohydrate diet, triglyceride levels decreased more (P = 0.044) and high-density lipoprotein cholesterol levels decreased less (P = 0.025). As seen in the small group of persons with diabetes (n = 54) and after adjustment for covariates, hemoglobin A1c levels improved more for persons on the low-carbohydrate diet. These more favorable metabolic responses to a low-carbohydrate diet remained significant after adjustment for weight loss differences. Changes in other lipids or insulin sensitivity did not differ between groups.
  
  
  CONCLUSIONS
  These findings are limited by a high dropout rate (34%) and by suboptimal dietary adherence of the enrolled persons.
  
  
  CONCLUSIONS
  Participants on a low-carbohydrate diet had more favorable overall outcomes at 1 year than did those on a conventional diet. Weight loss was similar between groups, but effects on atherogenic dyslipidemia and glycemic control were still more favorable with a low-carbohydrate diet after adjustment for differences in weight loss.
authors.affiliation: Philadelphia Veterans Affairs Medical Center, University of Pennsylvania Medical Center, and Drexel University College of Medicine, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Linda
authors.initials: L
authors.lastname: Stern
authors.forename: Nayyar
authors.initials: N
authors.lastname: Iqbal
authors.forename: Prakash
authors.initials: P
authors.lastname: Seshadri
authors.forename: Kathryn L
authors.initials: KL
authors.lastname: Chicano
authors.forename: Denise A
authors.initials: DA
authors.lastname: Daily
authors.forename: Joyce
authors.initials: J
authors.lastname: McGrory
authors.forename: Monica
authors.initials: M
authors.lastname: Williams
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Gracely
authors.forename: Frederick F
authors.initials: FF
authors.lastname: Samaha
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism; D048909:Diabetes Complications; D003920:Diabetes Mellitus / Q000178:diet therapy; D018752:Diet, Fat-Restricted; D004038:Diet, Reducing; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007328:Insulin / Q000097:blood; D008055:Lipids / Q000097:blood; D008297:Male; D024821:Metabolic Syndrome / Q000150:complications / Q000178:diet therapy; D008875:Middle Aged; D009767:Obesity, Morbid / Q000150:complications / Q000178:diet therapy* / Q000378:metabolism; D010349:Patient Compliance; D010352:Patient Dropouts; D015431:Weight Loss
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates; D007328:Insulin; D008055:Lipids