Ketogenic Diet Linked to Improvements in Prediabetes and Fatty Liver Disease: Study - Video

A randomized clinical trial suggests that weight loss can improve metabolic health regardless of diet, but a ketogenic diet may offer additional benefits for blood sugar control and liver health in people with obesity, prediabetes and fatty liver disease.

Published in Cell Metabolism on August 27, the study from Washington University School of Medicine compared three diets: a very-low-carbohydrate ketogenic diet, a high-carbohydrate, low-fat plant-forward diet, and a Mediterranean diet.

The trial included 55 adults with metabolically unhealthy obesity, characterized by obesity, elevated blood sugar and excess liver fat. Participants received all their meals for about five months and met weekly with dietitians.

Participants in all three groups lost approximately 10% of their starting body weight. Muscle insulin sensitivity also improved by about 50%, suggesting that the weight loss itself was largely responsible for improving insulin resistance, regardless of the diet's carbohydrate and fat composition.

However, important differences emerged in liver health and blood sugar control.

Liver insulin sensitivity improved two to three times more with the ketogenic diet than with the other diets. Liver fat also fell by 67% with the ketogenic approach, compared with 45% in the Mediterranean and high-carbohydrate groups.

The ketogenic diet also reduced 24-hour blood glucose by 20%, compared with 8% with the other diets. Blood insulin levels decreased by 74% on the ketogenic diet, versus 44% with the Mediterranean diet and 27% with the high-carbohydrate diet.

Prediabetes was reversed in 50% of participants following the ketogenic diet, compared with 29% on the Mediterranean diet and 7% on the high-carbohydrate diet.

Researchers emphasize that any meaningful weight loss is beneficial for people with metabolic disease. However, the findings suggest that diet composition may provide additional benefits beyond weight loss, particularly for people with fatty liver and impaired blood sugar control.

REFERENCE: Petersen, M. C., et al. (2026) Effect of diet macronutrient content on the cardiometabolic response to weight loss: A randomized clinical trial. Cell Metabolism. DOI: 10.1016/j.cmet.2026.07.020.