A new study indicates that the ketogenic diet may offer significant advantages for liver and metabolic health compared to other popular dietary approaches. Researchers found that individuals following a keto diet experienced greater reductions in liver fat and improvements in metabolic markers than those on Mediterranean or plant-forward diets.
The research involved participants with obesity, pre-diabetes, and fatty liver disease who were randomly assigned to one of three diets: ketogenic, Mediterranean, or plant-forward. All participants received prepared meals and were guided to lose approximately 10% of their body weight over four to five months. While all diets contributed to weight loss, reduced body fat, and improved insulin sensitivity and blood sugar control, the ketogenic diet demonstrated superior outcomes for liver health.
Participants on the keto diet saw an average reduction in liver fat of 67%, significantly higher than the 45% reduction observed in both the Mediterranean and plant-forward groups. The study also noted the largest increase in glucagon, a hormone that aids liver fat loss, and the most substantial reduction in blood insulin levels among the keto group. Notably, despite consuming the highest amount of fat, keto dieters did not experience an increase in blood fat or cholesterol levels, a finding that surprised researchers.
The ketogenic diet, characterized by high fat intake and severe carbohydrate restriction (around 4% of calories), forces the body to burn fat for energy. In contrast, the plant-forward diet emphasizes carbohydrates (about 70% of calories) and minimizes fat, while the Mediterranean diet falls between the two with a balanced intake of macronutrients.
Researchers highlighted that excess body fat can increase fatty acid release into the bloodstream, which the liver absorbs, potentially leading to non-alcoholic fatty liver disease (NAFLD). NAFLD can progress to inflammation, damage, scarring, and in severe cases, cirrhosis. The keto diet's effectiveness in reducing liver fat is therefore a significant finding for individuals with or at risk of this condition.
While the study points to notable benefits of the keto diet for liver and metabolic health, it also acknowledges the diet's challenges. The restrictive nature of severely limiting carbohydrates can be difficult to maintain long-term. Potential drawbacks include nutrient deficiencies, calorie depletion, and the onset of "keto flu" symptoms like fatigue and irritability. There are also ongoing discussions about the long-term impact of keto on heart disease risk and other health concerns.
Experts recommend consulting with a doctor or a registered dietitian to determine the most suitable dietary changes for individual health needs, especially when considering significant dietary shifts like the ketogenic diet.