Tay 2014.

Study characteristics
Methods	Review comparison(s) addressed by this study: 3 Study design: RCT, parallel, single‐centre (1) Trial registry number: ACTRN12612000369820 Total number of trial arms: 2 Year trial started: 2012 Sample size calculation: Yes Outcome(s) used for sample size calculation: Difference in HbA1c Duration of run‐in period (weeks): NA What was the duration of the weight loss phase: 2 years What was the duration of the weight maintenance phase: NA Other notes about methods: NA
Participants	Country and setting: Australia, outpatient research organisation in Adelaide. Key food representative of the macronutrient composition, and totalling 30% of energy, were provided to participants for the first twelve weeks; and key foods or a 50 AUD voucher on alternate months following the 12 weeks. Eligibility criteria: Participants were aged 35 to 68 years and were overweight or obese (defined as BMI of 26 to 45 kg/m2) with type 2 diabetes, defined as HbA1c ≥ 7.0% or treated with diabetes medication. Participants were excluded if they had type 1 diabetes, impaired renal function or proteinuria; had abnormal liver function test or any overt endocrine problems (except treated and stable thyroid disease); history of malignancy; respiratory, gastrointestinal or cardiovascular disease; were pregnant or lactating; had clinical depression; had a history of or current eating disorder, or were an ex or current smoker. Type 2 diabetes at baseline: Yes Impaired glucose tolerance at baseline: No Cardiovascular conditions/risk factors/events at baseline: No Gender: Mixed Total number randomised: 131 Total attrition in trial: 38 Treatment diet Participants randomised: 64 Participants withdrawn (voluntary): 13 Total attrition: 18 Control diet: Participants randomised: 67 Participants withdrawn (voluntary): 13 Total attrition: 20 Baseline data treatment diet: Randomised participants not included: 6/64 Age (years): mean (SD) 58 (7) Gender distribution (as reported): female 21/58 (36%), male 37/58 (64%) Weight (kg): mean (SD) 101.7 (14.4) BMI (kg/m2): mean (SD) 34.2 (4.5) DBP (mmHg): mean (SD) 80.0 (8.9) SBP (mmHg): mean (SD) 130.4 (13.1) HbA1c (%): mean (SD) 7.3 (1.1) LDL (mmol/L): mean (SD) 2.5 (0.9) HDL (mmol/L): mean (SD) 1.2 (0.2) Non‐HDL (mmol/L): NR TC (mmol/L): mean (SD) 4.5 (1.0) TG (mmol/L): mean (SD) 1.6 (0.7) Baseline data control diet: Randomised participants not included: 10/67 Age (years): mean (SD) 58 (7) Gender distribution (as reported): female 28/57 (49%), male 29/57 (51%) Weight (kg): mean (SD) 101.6 (15.8) BMI (kg/m2): mean (SD) 35.1 (4.1) DBP (mmHg): mean (SD) 80.8 (10.1) SBP (mmHg): mean (SD) 132.6 (13.2) HbA1c (%): mean (SD) 7.4 (1.1) LDL (mmol/L): mean (SD) 2.4 (0.9) HDL (mmol/L): mean (SD) 1.3 (0.3) Non‐HDL (mmol/L): NR TC (mmol/L): mean (SD) 4.3 (1.0) TG (mmol/L): mean (SD) 1.4 (0.6) Group differences at baseline: No Characteristic(s) with significant group difference and relevant statistic: NA 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: Low‐carbohydrate (LC) diet. Planned macronutrient profiles of 14% carbohydrate (with the objective of restricting to < 50 g/d), 28% protein and 58% total fat (35% MUFA, 13% PUFA and < 10% saturated) plus structured exercise 60 min on three nonconsecutive days. Individualised energy prescription with moderate restriction (500–1000 kcal/day) Treatment diet type (carbohydrate‐fat‐protein): Very low‐high‐high Exercise component? Yes Recipients: Subjects were 51% female, aged mean (SD) 58 (7) years, with BMI mean (SD) 35.1 (4.1), and weight 101.6 (15.8)kgs Why? LC diet with high–unsaturated and low–saturated fat content may promote greater improvements in glycaemic control in T2DM without detrimental effects on LDL‐C. What (materials)? Participants were supplied key foods or AU$50 food vouchers on alternate months. What (procedures)? LC diet, 14% of total energy as carbohydrate (objective to restrict intake to 50 g/day), 28% protein, and 58% total fat. Under supervision of exercise professionals, participants undertook, free of charge, 60‐min structured exercise classes on 3 nonconsecutive days per week, incorporating moderate exercise. Dietitians provided dietary advice and instruction on the eating plan and reporting requirements. Who provided? Dietitian How and where? Face‐to‐face individual sessions, location NR When and how much? Biweekly sessions for 12 weeks then monthly sessions Strategies to improve or maintain fidelity; tailoring and modification: Attendance records were kept and participants were encouraged to make up any missed sessions. Dietary intake and adherence were assessed from 7 consecutive days (including 2 weekend days) of daily weighed food records for every 14‐day period. To facilitate compliance, participants met individually with a dietitian biweekly for 12 weeks and monthly thereafter. Participants undertook, free of charge, 60‐min structured exercise classes. Extent of intervention fidelity: Energy intake did not differ between groups (HC 1587 +/‐ 171 kcal; P = 0.56). Relative to the HC diet group, the LC diet group consumed less carbohydrate (LC 56.7 +/‐ 8.0 vs. HC 204.9 +/‐ 22.8 g; 14 +/‐ 2 vs. 50 +/‐ 2% total energy) and dietary fibre (24.7 +/‐ 3.5 vs. 31.1 +/‐ 3.2 g), more protein (102.8 +/‐ 14.7 vs. 73.6 +/‐ 8.3 g; 27 +/‐ 1 vs. 19 +/‐ 1% total energy), total fat (96.5 +/‐ 16.5 vs. 44.3 +/‐ 7.4 g; 54 +/‐ 3 vs. 25 +/‐ 3% total energy), saturated fat (10.0 +/‐ 0.9 vs. 7.5 +/‐ 1.1% total energy), monounsaturated fat (30.4 +/‐ 1.8 vs. 11.5 +/‐ 1.3% total energy), polyunsaturated fat (12.2 +/‐ 1.1 vs. 4.1 +/‐ 0.6% total energy), and cholesterol (243 +/‐ 42 vs. 138 +/‐ 25 mg); P < 0.001 for all. Concomitant interventions: After 24 weeks, the LC diet group experienced twofold greater reductions in the antiglycaemic MES, with more participants experiencing a reduction of 20% compared with HC diet group (P < 0.005). Six participants reduced (LC 4 and HC 2) and five increased (LC 3 and HC 2) lipid‐lowering medication. Eleven participants reduced (LC 10 and HC 1) and six increased (LC 3 and HC 3) antihypertensive medication. Control diet: Name (as reported) and brief description: High‐carbohydrate (HC) diet. Planned macronutrient profiles of 53% carbohydrate with emphasis on low GI foods, 17% protein and < 30% total fat (15% MUFA, 9% PUFA and < 10% saturated) plus structured exercise 60 min on three nonconsecutive days. Individualised energy prescription with moderate restriction (500–1000 kcal/day) Control diet type (carbohydrate‐fat‐protein): Balanced‐balanced‐balanced Exercise component? Yes Recipients: Subjects were 36% female, aged mean (SD) 58 (7) years, with BMI mean (SD) 34.2 (4.5), and weight 101.7 (14.4)kgs. Why? NR What (materials)? Participants were supplied key foods or AU$50 food vouchers on alternate months. What (procedures)? HC diet, 53% carbohydrate with emphasis on low–glycaemic index foods, 17% protein, and 30% total fat. Under supervision of exercise professionals, participants undertook, free of charge, 60‐min structured exercise classes on 3 nonconsecutive days per week, incorporating moderate exercise. Dietitians provided dietary advice and instruction on the eating plan and reporting requirements. Who provided? Dietitian How and where? Face‐to‐face individual sessions, location NR When and how much? Biweekly sessions for 12 weeks then monthly sessions Strategies to improve or maintain fidelity; tailoring and modification: Attendance records were kept and participants were encouraged to make up any missed sessions. Dietary intake and adherence were assessed from 7 consecutive days (including 2 weekend days) of daily weighed food records for every 14‐day period. To facilitate compliance, participants met individually with a dietitian biweekly for 12 weeks and monthly thereafter. Participants undertook, free of charge, 60‐min structured exercise classes. Extent of intervention fidelity: Energy intake did not differ between groups (HC 1587 +/‐ 171 kcal; P = 0.56) Relative to the HC diet group, the LC diet group consumed less carbohydrate (LC 56.7 +/‐ 8.0 vs. HC 204.9 +/‐ 22.8 g; 14 +/‐ 2 vs. 50 +/‐ 2% total energy) and dietary fibre (24.7 +/‐ 3.5 vs. 31.1 +/‐ 3.2 g), more protein (102.8 +/‐ 14.7 vs. 73.6 +/‐ 8.3 g; 27 +/‐ 1 vs. 19 +/‐ 1% total energy), total fat (96.5 +/‐ 16.5 vs. 44.3 +/‐ 7.4 g; 54 +/‐ 3 vs. 25 +/‐ 3% total energy), saturated fat (10.0 +/‐ 0.9 vs. 7.5 +/‐ 1.1% total energy), monounsaturated fat (30.4 +/‐ 1.8 vs. 11.5 +/‐ 1.3% total energy), polyunsaturated fat (12.2 +/‐ 1.1 vs. 4.1 +/‐ 0.6% total energy), and cholesterol (243 +/‐ 42 vs. 138 +/‐ 25 mg); P < 0.001 for all. Concomitant interventions: After 24 weeks, the LC diet group experienced twofold greater reductions in the antiglycaemic MES, with more participants experiencing a reduction of 20% compared with HC diet group (P < 0.005). Six participants reduced (LC 4 and HC 2) and five increased (LC 3 and HC 2) lipid‐lowering medication. Eleven participants reduced (LC 10 and HC 1) and six increased (LC 3 and HC 3) antihypertensive medication.
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: Yes
Notes	Number and type of records(s): journal article Trial acronym/name: None Trial funded by: National Health and Medical Research Council project grant 103415 Declaration of interest: "No potential conflicts of interest relevant to this article were reported."