WASHINGTON, D.C. — Adults with type 2 diabetes who followed a low-fat vegan diet for 16 weeks, eating as much as they wanted, with no calorie counting or portion control, lost weight, reduced fat buildup in the liver and abdomen, and improved insulin sensitivity and beta-cell function, according to a new clinical trial published in BMJ Open Diabetes Research & Care .
The study, led by researchers at the Physicians Committee for Responsible Medicine, in collaboration with the Yale School of Medicine, is the first to simultaneously measure liver fat, muscle fat, visceral fat, and tissue advanced glycation end-products (AGEs) in a single plant-based dietary intervention in people with type 2 diabetes, offering a more complete picture of how diet reverses the underlying mechanisms that drive the disease.
“For years, people with diabetes have been told to count calories and measure portions. This study shows that a simple shift in what you eat—toward vegetables, whole grains, legumes, and fruit—can reduce the fat clogging the liver by a third and improve how the pancreas makes insulin, without anyone having to count a single calorie,” said Hana Kahleova, MD, PhD, the lead author of the study and director of clinical research at the Physicians Committee for Responsible Medicine.
Key Findings
“This research adds to a growing body of evidence that food can work like medicine for people with diabetes. When patients don't have to weigh their portions or track every calorie, healthy eating becomes something they can actually sustain, and that is when we see real, lasting metabolic change,” said Dr. Kahleova.
Founded in 1985, the Physicians Committee for Responsible Medicine is a nonprofit organization that promotes preventive medicine, conducts clinical research, and encourages higher standards for ethics and effectiveness in education and research.
BMJ Open Diabetes Research & Care
Randomized controlled/clinical trial
People
Changes in ectopic lipids, insulin sensitivity, and beta cell function after a low-fat vegan diet in adults with type 2 diabetes: a 16-week single-arm clinical trial
8-Oct-2026