a1 School of Biomedical and Molecular Sciences, University of Surrey, Guildford, Surrey, GU2 7XH, UK
a2 Queen Margaret University College, Edinburgh EH12 8TS, UK
a3 Department of Exercise, Nutrition and Health Sciences, University of Bristol, Bristol BS8 1TP, UK
a4 Northern Ireland Centre for Food and Health, University of Ulster, Coleraine BT52 1SA, UK
a5 School of Biomedical Sciences, University of Nottingham, Nottingham NG7 2UH, UK
Objective To investigate the relative efficacy of four popular weight-loss programmes on plasma lipids and lipoproteins as measures of CVD risk.
Design A multi-centred, randomised, controlled trial of four diets – Dr Atkins’ New Diet Revolution, The Slim-Fast Plan, Weight Watchers Pure Points programme and Rosemary Conley’s ‘Eat yourself Slim’ Diet and Fitness Plan – against a control diet, in parallel for 6 months.
Setting and subjects The trial was conducted at five universities across the UK (Surrey, Nottingham, Ulster (Coleraine), Bristol and Edinburgh (Queen Margaret University College)) and involved the participation of 300 overweight and obese males and females aged 21–60 years in a community setting.
Results Significant weight loss was achieved by all dieting groups (5–9 kg at 6 months) but no significant difference was observed between diets at 6 months. The Weight Watchers and Rosemary Conley (low-fat) diets were followed by significant reductions in plasma LDL cholesterol (both −12·2 % after 6 months, P < 0·01), whereas the Atkins (low-carbohydrate) and Weight Watchers diets were followed by marked reductions in plasma TAG (–38·2 % and –22·6 % at 6 months respectively, P < 0·01). These latter two diets were associated with an increase in LDL particle size, a change that has been linked to reduced CVD risk.
Conclusions Overall, these results demonstrate the favourable effects of weight loss on lipid-mediated CVD risk factors that can be achieved through commercially available weight-loss programmes. No detrimental effects on lipid-based CVD risk factors were observed in participants consuming a low-carbohydrate diet.
(Received July 26 2007)
(Accepted May 07 2008)