A whole-food, plant-based intensive lifestyle intervention improves glycaemic control and reduces medications in individuals with type 2 diabetes: a randomised controlled trial

Aims/hypothesis: We conducted the largest and longest clinical trial comparing a whole-food, plant-based intervention with standard medical care (SMC) in individuals with type 2 diabetes.

Methods: We randomised (parallel-arm; computerised 1:1 randomisation ratio) 169 adults aged 18-75 years with type 2 diabetes in the Marshall Islands to an intensive whole-food, plant-based intervention with moderate exercise (PB+Ex) or SMC for 24 weeks. The PB+Ex intervention included 12 weeks of meals, exercise sessions and group classes. Primary outcomes were glycaemic control (HbA_1c, glucose, insulin and HOMA-IR) and glucose-lowering medication use. Secondary outcomes included lipids, blood pressure, heart rate and C-reactive protein. Only lab analysts were blinded.

Results: Compared with SMC (n=90 randomised; n=70 analysed), the PB+Ex (n=79 randomised; n=66 analysed) intervention decreased HbA_1c by an additional 14 mmol/mol (1.3%) at week 12 (-22 vs -7 mmol/mol [-2.0% vs -0.7%]; p<0.0001) and 8 mmol/mol (0.7%) at week 24 (-16 vs -8 mmol/mol [-1.4% vs -0.7%]; p=0.01). Concomitantly, 63% of medicated PB+Ex participants reduced their glucose-lowering medications (vs 24%; p=0.006), and 23% of PB+Ex participants with a baseline HbA_1c <75 mmol/mol (<9%) achieved remission. Additionally, the PB+Ex intervention reduced weight (-2.7 kg; p<0.0001), C-reactive protein (-11 nmol/l; p=0.005) and cardiovascular medication use compared with SMC. At intermediate timepoints, it improved glucose, insulin, HOMA-IR, cholesterol, triglycerides and heart rate, but not at week 24.

Conclusions/interpretation: A whole-food, plant-based lifestyle intervention was more effective for improving glycaemic control than SMC. It also reduced the need for diabetes and cardiovascular medications and induced diabetes remission in some participants. Therefore, it is an effective, evidence-based lifestyle option for individuals with type 2 diabetes.

Trial registration: ClinicalTrials.gov NCT03862963 FUNDING: This research was funded by the Department of the Army (W81XWH-05-1-0547). CJH received support through a National Institutes of Health Predoctoral T32 Obesity Fellowship (T32 HL105349).