Lasker 2008.

Study characteristics
Methods	Review comparison(s) addressed by this study: 1 Study design: RCT, parallel, single‐centre (1) Trial registry number: NR Total number of trial arms: 2 Year trial started: NR Sample size calculation: Yes Outcome(s) used for sample size calculation: Change in 2‐hour post‐prandial insulin sensitivity (INS) Duration of run‐in period (weeks): NA What was the duration of the weight loss phase: 4 months What was the duration of the weight maintenance phase: NA Other notes about methods: NA
Participants	Country and setting: USA, outpatient research laboratory in Urbana‐Champaign Eligibility criteria: Participants were adults. They were excluded if their BMI was below 26 kg/m2 or weight was above 140 kg; were smokers; had any existing medical condition requiring medication which may impact outcomes of the study; or used steroids or anti‐depressants. Type 2 diabetes at baseline: No Impaired glucose tolerance at baseline: Unclear Cardiovascular conditions/risk factors/events at baseline: Unclear Gender: Mixed Total number randomised: 65 Total attrition in trial: 15 Treatment diet Participants randomised: 32 Participants withdrawn (voluntary): NR Total attrition: 7 Control diet: Participants randomised: 33 Participants withdrawn (voluntary): NR Total attrition: 8 Baseline data treatment diet: Randomised participants not included: 7/32 Age (years): NR Gender distribution (as reported): NR Weight (kg): mean (SE) 96.6 (3.9) BMI (kg/m2): mean (SE) 33.8 (1.1) DBP (mmHg): NR SBP (mmHg): NR HbA1c (%): NR LDL (mmol/L): mean (SE) 3.41 (0.16) HDL (mmol/L): mean (SE) 1.14 (0.07) Non‐HDL (mmol/L): NR TC (mmol/L): mean (SE) 5.33 (0.19) TG (mmol/L): mean (SE) 1.72 (0.18) Baseline data control diet: Randomised participants not included: 8/33 Age (years): NR Gender distribution (as reported): NR Weight (kg): mean (SE) 94.3 (2.1) BMI (kg/m2): mean (SE) 33.4 (0.7) DBP (mmHg): NR SBP (mmHg): NR HbA1c (%): NR LDL (mmol/L): mean (SE) 3.49 (0.13) HDL (mmol/L): mean (SE) 1.27 (0.07) Non‐HDL (mmol/L): NR TC (mmol/L): mean (SE) 5.52 (0.17) TG (mmol/L): mean (SE) 1.66 (0.17) Group differences at baseline: Yes Characteristic(s) with significant group difference and relevant statistic: characteristic 1: insulin (P < 0.05); intervention vs control Other notes about participants: NA
Interventions	Energy (E) comparison of treatment vs control diets: Similar energy prescription/approach to restrict energy intake in both diets Treatment diet: Name (as reported) and brief description: PRO diet. Prescribed dietary protein at 1.6 g/kg/d (~30% of energy intake) and carbohydrate < 170 g/d (~40% of energy) and dietary lipids ~30% energy intake. Recommendation for 30 min of walking 5 d/week. Energy prescription of 7100 kJ/d Treatment diet type (carbohydrate‐fat‐protein): Low‐balanced‐high Exercise component? Yes Recipients: N = 25 (gender NR) with mean (SEM) weight 96.6 (3.9) kg, mean (SEM) BMI 33.8 (1.1) kg/m2, mean (SEM) total cholesterol 5.33 (0.19) mmol/L, mean (SEM) LDL 3.41 (0.16), mean (SEM) HDL 1.14 (0.07) mmol/L, mean (SEM) triglycerides 1.72 (0.18) mmol/L Why? "Reducing carbohydrate intake with replacement of either fat or protein has been shown to reduce TAG and increase HDL‐C even under weight stable conditions. Substitution with protein may be more beneficial than fat for lipid changes and improvement in INS action. Indeed, independent effects of protein on glycemic regulation suggests protein may be a more effective dietary change than increases in fat intake for reducing risk for metabolic disease." What (materials)? "Each group received a menu plan with meals for each day meeting established nutritional requirements and dietary lipid guidelines. Subjects were provided electronic food scales and instructed to weigh foods at all meals."  Armband accelerometers also provided What (procedures)? The prescribed PRO diet provided dietary protein at 1.6 g/kg‐1/d‐1 and < 170 g/d carbohydrate (~30% and ~40% of energy intake, respectively). Dietary lipids were constant between diets (~30% energy intake). For the PRO group, education guidelines emphasised use of high‐quality proteins including lean meats, dairy and eggs. Both diets included 5 servings/d of vegetables and 2 to 3 servings/d of fruit. After baseline data collection, subjects received instructions from a research dietitian about their specific diet including menus, food substitutions, portion sizes, and procedures for maintaining weighed diet records. Activity guidelines emphasised lifestyle recommendations for physical activity based on NIH Guidelines for Weight Management. These guidelines recommend a minimum of 30 min of walking 5 d/wk. Participation in physical activity for the groups was voluntary. Physical activity was monitored using daily activity logs and 3 d/mo subjects wore armband accelerometers (BodyMedia, Cincinnati, OH). Activity logs were collected each week. Subjects also attended 1‐hour meetings for 4 months. Who provided? Dietitian How and where? Face‐to‐face at the nutrition research facility When and how much? Diet intervention lasted for 4 months. At baseline instructions on diet including menus, food substitutions, portion sizes, and procedures for maintaining weight records. Over 4 months, weekly 1‐hr group meetings with dietitian who provided diet and exercise information and reviewed diet records for treatment compliance. Weekly weight checks were done. Physical activity was monitored using daily activity logs and armband accelerometers. At the end of 4 months blood tests were conducted fasting and 1‐ and 2‐hr post‐prandial as a meal challenge. Strategies to improve or maintain fidelity; tailoring and modification: "Nutrient intakes were evaluated as mean daily intakes from 3‐d weighed records using Nutritionist Pro software (First DataBank Inc. 2003, San Bruno, CA) to improve compliance." Extent of intervention fidelity: NR Concomitant interventions: NR Control diet: Name (as reported) and brief description: CHO diet. Provided dietary protein equal to 0.8 g/kg/d (~15% of energy intake) and carbohydrate 220 g/d (~55% of energy) and total fat ~30% of energy intake. Recommendation for 30 min of walking 5 d/week.  Energy prescription of 7100 kJ/d Control diet type (carbohydrate‐fat‐protein): Balanced‐balanced‐balanced Exercise component? Yes Recipients: N = 25 (gender NR) with mean (SEM) weight 94.3 (2.1) kg, mean (SEM) BMI 33.4 (0.7) kg/m2, mean (SEM) total cholesterol 5.52 (0.17) mmol/L, mean (SEM) LDL 3.49 (0.13), mean (SEM) HDL 1.27 (0.07) mmol/L, mean (SEM) triglycerides 1.66 (0.17) mmol/L Why? To assess whether conventionally accepted carbohydrate is better then moderate‐carbohydrate diet at achieving greater fat mass loss and more favourable changes in post‐prandial insulin response and features of dyslipidaemia What (materials)? "Each group received a menu plan with meals for each day meeting established nutritional requirements and dietary lipid guidelines. Subjects were provided electronic food scales and instructed to weigh foods at all meals." Armband accelerometers also provided What (procedures)? The prescribed CHO diet provided dietary protein at 0.8 g/kg‐1/d‐1 and > 220 g/d carbohydrate (~15% and ~55% of energy intake respectively). Education guidelines for the CHO group followed USDA MyPyramid and emphasised restricting dietary fat and cholesterol with use of whole grain breads, rice, cereals and pasta. Both diets included 5 servings/d of vegetables and 2 to 3 servings/d of fruit. After baseline data collection, subjects received instructions from a research dietitian about their specific diet including menus, food substitutions, portion sizes, and procedures for maintaining weighed diet records. Activity guidelines emphasised lifestyle recommendations for physical activity based on NIH Guidelines for Weight Management. These guidelines recommend a minimum of 30 min of walking 5 d/wk. Participation in physical activity for the groups was voluntary. Physical activity was monitored using daily activity logs and 3 d/mo subjects wore armband accelerometers (BodyMedia, Cincinnati, OH). Activity logs were collected each week. Who provided? Dietitian How and where? Face‐to‐face at the nutrition research facility When and how much? Diet intervention lasted for 4 months. At baseline instructions on diet including menus, food substitutions, portion sizes, and procedures for maintaining weight records. Over 4 months, weekly 1‐hr group meetings with dietitian who provided diet and exercise information and reviewed diet records for treatment compliance. Weekly weight checks were done. Physical activity was monitored using daily activity logs and armband accelerometers. At the end of 4 months blood tests were conducted fasting and 1‐ and 2‐hr post‐prandial as a meal challenge Strategies to improve or maintain fidelity; tailoring and modification: "Nutrient intakes were evaluated as mean daily intakes from 3‐d weighed records using Nutritionist Pro software (First DataBank Inc. 2003, San Bruno, CA) to improve compliance." Extent of intervention fidelity: NR Concomitant interventions: NR
Outcomes	Change in body weight (kg) at 3 to < 12 months: Yes Change in body weight (kg) at ≥ 12 months: No Number of participants with 5% weight loss from baseline at 3 to < 12 months: No Number of participants with 5% weight loss from baseline at ≥ 12 months: No Change in BMI (kg/m2) at 3 to 12 months: Yes Change in BMI (kg/m2) at ≥ 12 months: No Number of participants with 5% BMI reduction from baseline at 3 to 12 months: No Number of participants with 5% BMI reduction from baseline at ≥ 12 months: No Change in DBP (mmHg) at ≥ 12 months: No Change in SBP (mmHg) at ≥ 12 months: No All‐cause mortality at ≥ 12 months: No Cardiovascular mortality at ≥ 12 months: No Non‐fatal myocardial infarction at ≥ 12 months: No Non‐fatal stroke at ≥ 12 months: No Diagnosis of type 2 diabetes mellitus at ≥ 12 months: No Change in HbA1c (%) at ≥ 12 months: No Change in LDL (mmol/L) at ≥ 12 months: No Change in HDL (mmol/L) at ≥ 12 months: No Change in non‐HDL (mmom/L) at ≥ 12 months: No Change in total cholesterol (TC) (mmol/L) at ≥ 12 months: No Change in triglycerides (or triacylglycerides) (TG) (mmol/L) at ≥ 12 months: No Participant‐reported adverse effects: No
Notes	Number and type of records(s): journal article Trial acronym/name: None Trial funded by: National Cattleman's Beef Association, The Beef Board and Kraft Foods Declaration of interest: "DKL received grant/research support from the funding agencies for this research: the National Cattleman's Beef Association, The Beef Board and Kraft Foods."