Keto diet reduced liver fat by 67% in clinical trial

A clinical trial by Washington University School of Medicine, published in Cell Metabolism on August 27, 2026, reveals that a ketogenic diet reduces liver fat by 67% in people with obesity, prediabetes, and fatty liver disease. This outperforms the 45% reduction seen in Mediterranean and low-fat diets. Furthermore, 50% of keto participants reversed their prediabetes, compared to 29% on the Mediterranean diet and 7% on the plant-forward diet, without experiencing increases in blood fat or cholesterol.

Ketogenic diet clinical trial

• ▪A clinical trial published on August 27, 2026, in Cell Metabolism found that a ketogenic diet may provide stronger metabolic benefits for people with obesity than a Mediterranean or low-fat diet
• ▪The clinical trial comparing the ketogenic, Mediterranean, and low-fat diets was conducted by researchers at the Washington University School of Medicine in St. Louis, Missouri

Comparative diet study design

• ▪The ketogenic diet in the Washington University School of Medicine clinical trial supplied 4% of calories from carbohydrates and 73% from fat, compared to 50% carbohydrates and 35% fat for the Mediterranean diet, and 70% carbohydrates and 15% fat for the plant-forward diet
• ▪In the Washington University School of Medicine clinical trial, researchers supplied all food and adjusted calorie intake so that participants in all three diet groups would lose approximately 10% of their body weight over four to five months
• ▪The Washington University School of Medicine clinical trial enrolled 42 participants with obesity, prediabetes, and fatty liver disease, randomly assigning them to follow a ketogenic, Mediterranean, or low-fat, plant-forward diet

Liver fat reduction outcomes

• ▪Despite consuming the most fat, participants in the ketogenic diet group of the Washington University School of Medicine clinical trial did not experience an increase in blood fat or cholesterol levels, according to first author Max Petersen
• ▪Participants on the ketogenic diet in the Washington University School of Medicine clinical trial experienced an average liver fat reduction of 67%, compared to an average reduction of 45% in both the Mediterranean and plant-forward diet groups

Metabolic health improvements

• ▪Corresponding author Samuel Klein of the Washington University School of Medicine stated that reducing carbohydrate intake can have therapeutic effects on metabolism beyond weight loss alone for individuals with high liver fat and prediabetes
• ▪By the end of the four-to-five-month Washington University School of Medicine clinical trial, participants in all three diet groups significantly reduced their body fat and improved their insulin sensitivity

Prediabetes reversal rates

• ▪Following the weight loss intervention in the Washington University School of Medicine clinical trial, approximately 50% of participants on the ketogenic diet no longer met the criteria for prediabetes
• ▪In comparison to the ketogenic group's 50% prediabetes reversal rate in the Washington University School of Medicine clinical trial, 29% of participants on the Mediterranean diet and 7% on the plant-forward diet no longer met prediabetes criteria

Glucagon and insulin changes

• ▪Participants in the ketogenic diet group of the Washington University School of Medicine clinical trial showed the largest rise in glucagon, a hormone that helps reduce fat stored in the liver, compared to the other two diet groups
• ▪The ketogenic diet group in the Washington University School of Medicine clinical trial experienced the greatest decline in blood insulin levels over a 24-hour tracking period compared to the Mediterranean and plant-forward groups

2 sources