Haufe 2013.

Study characteristics
Methods	Review comparison(s) addressed by this study: 1, 2 Study design: RCT, parallel, single‐centre (1) Trial registry number: NCT00956566 Total number of trial arms: 2 Year trial started: 2007 Sample size calculation: Yes Outcome(s) used for sample size calculation: Weight loss Duration of run‐in period (weeks): NA What was the duration of the weight loss phase: 6 months What was the duration of the weight maintenance phase: 17 to 36 months (average 24 months) Other notes about methods: NA
Participants	Country and setting: Germany, outpatient academic clinical research centre in Berlin Eligibility criteria: Participants who were overweight or obese, but otherwise healthy. Participants were excluded if they did more than two hours of physical activity per week; consumed more than 20 g of alcohol per day; had type 2 diabetes, acute or chronic infections; were pregnant or nursing. Type 2 diabetes at baseline: No Impaired glucose tolerance at baseline: Mixed Cardiovascular conditions/risk factors/events at baseline: No Gender: Mixed Total number randomised: 170 Total attrition in trial: 68 Treatment diet Participants randomised: 84 Participants withdrawn (voluntary): 20 Total attrition: 32 Control diet: Participants randomised: 86 Participants withdrawn (voluntary): 24 Total attrition: 36 Baseline data treatment diet: Randomised participants not included: 32/84 (except for age, weight and BMI 29/84) Age (years): mean (SD) 43 (9) Gender distribution (as reported): female 44/52, male 8/52 Weight (kg): mean (SD) 94 (15) BMI (kg/m2): mean (SD) 33.4 (4.2) DBP (mmHg): NR SBP (mmHg): NR HbA1c (%): NR LDL (mmol/L): mean (SD) 2.92 (0.64) HDL (mmol/L): mean (SD) 1.52 (0.73) Non‐HDL (mmol/L): NR TC (mmol/L): mean (SD) 4.85 (0.66) TG (mmol/L): mean (SD) 1.14 (0.49) Baseline data control diet: Randomised participants not included: 36/86 (except for age, weight and BMI 32/86) Age (years): mean (SD) 45 (9) Gender distribution (as reported): female 40/50, male 10/50 Weight (kg): mean (SD) 93 (19) BMI (kg/m2): mean (SD) 33.5 (4.3) DBP (mmHg): NR SBP (mmHg): NR HbA1c (%): NR LDL (mmol/L): mean (SD) 3.15 (0.89) HDL (mmol/L): mean (SD) 1.38 (0.56) Non‐HDL (mmol/L): NR TC (mmol/L): mean (SD) 4.9 (0.95) TG (mmol/L): mean (SD) 1.20 (0.63) Group differences at baseline: No Characteristic(s) with significant group difference and relevant statistic: NA Other notes about participants: All baseline characteristics are reported by trial arm and intrahepatic lipids; these were combined to give characteristics by trial arm only.
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: Reduced‐carbohydrate diet. Aimed at achieving ≤ 90 g/d of carbohydrates, 0.8 g protein per kg body weight and a minimum of 30% fat. Total energy prescription of 30% less than baseline intake (to a minimum of 1200 kcal/day) Treatment diet type (carbohydrate‐fat‐protein): Low‐unclear‐high Exercise component? No Recipients: Participants were 84.6% female, aged 43.15 (8.67) years, with BMI 33.38 (4.24) and weight 92.85 (14.81) kg Why? Weight reduction through caloric restriction decreases hepatic fat up to 12 months and improves insulin sensitivity while preventing type 2 diabetes. What (materials)? NR What (procedures)? Participants followed a reduced energy diet with nutritional counselling to a reduced‐carbohydrate diet, with regular group sessions and analysis of seven‐day food protocols. Who provided? Group sessions and individual counselling, with food protocol analysis, were run by nutritionists. How and where? Face‐to‐face group sessions and individual face‐to‐face sessions, location NR. Telephonic check‐ins on weight changes were done in the weight maintenance phase. When and how much? The active intervention duration was six months, with follow‐up after weight maintenance of between 17 and 36 months [from 18 Haufe 2011]. Group sessions occurred on a weekly basis throughout the active weight loss phase, with individual counselling occurring every two months in this phase. An analysis of seven‐day food protocol was conducted at every individual counselling. No active intervention occurred in the weight maintenance phase. Strategies to improve or maintain fidelity; tailoring and modification: Group sessions, follow‐up measurement of body weight, keeping of food protocols, adherence monitoring in individual sessions Extent of intervention fidelity: The authors reported that participants adhered to their assigned intervention. Concomitant interventions: "They [participants] ingested no medications." Control diet: Name (as reported) and brief description: Reduced‐fat diet. Aimed at achieving a fat content of ≤ 20% of total energy intake, 0.8 g protein per kg body weight and the remaining energy content provided by carbohydrates. Author reported via email that this group ingested 53.7% carbohydrates. Total energy prescription of 30% less than baseline intake (to a minimum of 1200 kcal/day) Control diet type (carbohydrate‐fat‐protein): Balanced‐low‐high Exercise component? No Recipients: Participants were 80.0% female, aged 45.08 (8.96) years, with BMI 32.98 (3.55) and weight 92.32 (17.2) kg. Why? Low‐fat caloric restriction diets reduce the hepatic fat content in humans. What (materials)? NR What (procedures)? Participants followed a reduced energy diet with nutritional counselling to a reduced‐fat diet, with regular group sessions and analysis of seven‐day food protocols. Who provided? Group sessions and individual counselling, with food protocol analysis, were run by nutritionists. How and where? Face‐to‐face group sessions and individual face‐to‐face sessions, location NR. Telephonic check‐ins on weight changes were done in the weight maintenance phase. When and how much? The active intervention duration was six months, with follow‐up after weight maintenance of between 17 and 36 months [from 18 Haufe 2011]. Group sessions occurred on a weekly basis throughout the active weight loss phase, with individual counselling occurring every two months in this phase. An analysis of seven‐day food protocol was conducted at every individual counselling. No active intervention occurred in the weight maintenance phase. Strategies to improve or maintain fidelity; tailoring and modification: Group sessions, follow‐up measurement of body weight, keeping of food protocols, adherence monitoring in individual sessions Extent of intervention fidelity: The authors reported that participants adhered to their assigned intervention. Concomitant interventions: "They [participants] ingested no medications."
Outcomes	Change in body weight (kg) at 3 to < 12 months: Yes Change in body weight (kg) at ≥ 12 months: Yes 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: Yes 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: Yes Change in HDL (mmol/L) at ≥ 12 months: Yes Change in non‐HDL (mmom/L) at ≥ 12 months: No Change in total cholesterol (TC) (mmol/L) at ≥ 12 months: Yes Change in triglycerides (or triacylglycerides) (TG) (mmol/L) at ≥ 12 months: Yes Participant‐reported adverse effects: No
Notes	Number and type of records(s): journal article Trial acronym/name: B‐SMART Trial funded by: Federal Ministry of Education and Research (BMBF‐0313868) Declaration of interest: "No potential conflicts of interest relevant to this article were reported."