title: Effects of low-carbohydrate diets v. low-fat diets on body weight and cardiovascular risk factors: a meta-analysis of randomised controlled trials.
abstract: The effects of low-carbohydrate (LC) diets on body weight and cardiovascular risk are unclear, and previous studies have found varying results. Our aim was to conduct a meta-analysis of randomised controlled trials (RCT), assessing the effects of LC diets v. low-fat (LF) diets on weight loss and risk factors of CVD. Studies were identified by searching MEDLINE, Embase and Cochrane Trials. Studies had to fulfil the following criteria: a RCT; the LC diet was defined in accordance with the Atkins diet, or carbohydrate intake of <20% of total energy intake; twenty subjects or more per group; the subjects were previously healthy; and the dietary intervention had a duration of 6 months or longer. Results from individual studies were pooled as weighted mean difference (WMD) using a random effect model. In all, eleven RCT with 1369 participants met all the set eligibility criteria. Compared with participants on LF diets, participants on LC diets experienced a greater reduction in body weight (WMD -2·17 kg; 95% CI -3·36, -0·99) and TAG (WMD -0·26 mmol/l; 95% CI -0·37, -0·15), but a greater increase in HDL-cholesterol (WMD 0·14 mmol/l; 95% CI 0·09, 0·19) and LDL-cholesterol (WMD 0·16 mmol/l; 95% CI 0·003, 0·33). This meta-analysis demonstrates opposite change in two important cardiovascular risk factors on LC diets--greater weight loss and increased LDL-cholesterol. Our findings suggest that the beneficial changes of LC diets must be weighed against the possible detrimental effects of increased LDL-cholesterol.
authors.affiliation: 1Department of Nutrition,Institute of Basic Medical Sciences, Faculty of Medicine,University of Oslo,PO Box 1046 Blindern,0317 Oslo,Norway.
authors.forename: Nadia
authors.initials: N
authors.lastname: Mansoor
authors.affiliation: 1Department of Nutrition,Institute of Basic Medical Sciences, Faculty of Medicine,University of Oslo,PO Box 1046 Blindern,0317 Oslo,Norway.
authors.forename: Kathrine J
authors.initials: KJ
authors.lastname: Vinknes
authors.affiliation: 1Department of Nutrition,Institute of Basic Medical Sciences, Faculty of Medicine,University of Oslo,PO Box 1046 Blindern,0317 Oslo,Norway.
authors.forename: Marit B
authors.initials: MB
authors.lastname: Veierød
authors.affiliation: 1Department of Nutrition,Institute of Basic Medical Sciences, Faculty of Medicine,University of Oslo,PO Box 1046 Blindern,0317 Oslo,Norway.
authors.forename: Kjetil
authors.initials: K
authors.lastname: Retterstøl
mesh_terms: D001835:Body Weight; D002318:Cardiovascular Diseases / Q000517:prevention & control*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D016208:Databases, Factual; D050528:Diet, Carbohydrate-Restricted; D018752:Diet, Fat-Restricted; D002149:Energy Intake; D006801:Humans; D016032:Randomized Controlled Trials as Topic; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D014280:Triglycerides
keywords: CHO carbohydrates; Cardiovascular risk factors; DBP diastolic blood pressure; LC low CHO; LF low fat; Low-carbohydrate diets; Low-fat diets; RCT randomised controlled trials; SBP systolic blood pressure; TC total cholesterol; WMD weighted mean difference; Weight loss