title: The Diabetes Excess Weight Loss (DEWL) Trial: a randomised controlled trial of high-protein versus high-carbohydrate diets over 2 years in type 2 diabetes.
abstract: OBJECTIVE
  To compare the effectiveness of low-fat high-protein and low-fat high-carbohydrate dietary advice on weight loss, using group-based interventions, among overweight people with type 2 diabetes. Study design Multicentre parallel (1:1) design, blinded randomised controlled trial.
  
  
  METHODS
  Individuals with type 2 diabetes aged 30–75 years and a BMI >27 kg/m2 were randomised, by an independent statistician using sequentially numbered sealed envelopes, to be prescribed either a low-fat high-protein (30% of energy as protein, 40% as carbohydrate, 30% as fat) or a low-fat high carbohydrate(15% of energy as protein, 55%as carbohydrate,30% as fat) diet. Participants attended 18 group sessions over 12 months. Primary outcomes were change in weight and waist circumference assessed at baseline, 6 and 12 months.Secondary outcomes were body fatness, glycaemic control,lipid profile, blood pressure and renal function. A further assessment was undertaken 12 months after the intervention.Research assessors remained blinded to group allocation throughout. Intention-to-treat analysis was performed.
  
  
  RESULTS
  A total of 419 participants were enrolled (mean±SDage 58±9.5 years,BMI 36.6±6.5 kg/m2 and HbA1c 8.1±1.2%(65 mmol/mol)). The study was completed by 70%(294/419).No differences between groups were found in change in weight or waist circumference during the intervention phase or the 12-month follow-up. Both groups had lost weight (2–3 kg, p<0.001) and reduced their waist circumference (2–3 cm, p<0.001) by 12 months and largely maintained this weight loss for the following 12 months. By 6 months, the difference in self-reported dietary protein between groups was small (1.1%total energy; p<0.001). No significant differences between groups were found in secondary outcomes: body fatness, HbA1c, lipids, blood pressure and renal function.There were no important adverse effects.
  
  
  CONCLUSIONS
  In a 'real-world' setting, prescription of an energy-reduced low-fat diet, with either increased protein or carbohydrate, results in similar modest losses in weight and waist circumference over 2 years
authors.affiliation: Department of Medicine, University of Otago,Wellington, New Zealand. jeremy.krebs@ccdhb.org.nz
authors.forename: J D
authors.initials: JD
authors.lastname: Krebs
authors.forename: C R
authors.initials: CR
authors.lastname: Elley
authors.forename: A
authors.initials: A
authors.lastname: Parry-Strong
authors.forename: H
authors.initials: H
authors.lastname: Lunt
authors.forename: P L
authors.initials: PL
authors.lastname: Drury
authors.forename: D A
authors.initials: DA
authors.lastname: Bell
authors.forename: E
authors.initials: E
authors.lastname: Robinson
authors.forename: S A
authors.initials: SA
authors.lastname: Moyes
authors.forename: J I
authors.initials: JI
authors.lastname: Mann
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D003924:Diabetes Mellitus, Type 2 / Q000178:diet therapy* / Q000503:physiopathology; D004038:Diet, Reducing; D004040:Dietary Carbohydrates; D004044:Dietary Proteins; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome; D015431:Weight Loss / Q000502:physiology*
chemical_list: D004040:Dietary Carbohydrates; D004044:Dietary Proteins