A ketogenic diet improves liver health and metabolism in people with obesity more than other weight loss plans, according to researchers writing in Cell Metabolism.
The clinical trial showed that a keto diet reduced fat in the liver by an average of 67 percent, compared with a 45 percent reduction for both Mediterranean and low-fat diets, even when participants lost the exact same amount of weight.
Researchers conducted the trial with 42 adult participants who had obesity, prediabetes, and fatty liver disease. Participants were randomly assigned to three groups following a ketogenic diet, a Mediterranean diet, or a predominantly plant-based low-fat diet.
All meals and food items were provided directly by the research team to maintain consistent dietary control. Calorie levels were individually adjusted for each participant to achieve a target weight loss of about 10 percent over four to five months.
Reversal of prediabetes symptoms
While all three diets reduced total body fat and improved insulin sensitivity, the ketogenic regimen produced the most pronounced health improvements. Following weight loss, roughly 50 percent of participants in the keto group no longer met the clinical criteria for prediabetes, compared with 29 percent of those on the Mediterranean diet and 7 percent on the low-fat diet.
Prediabetes is a health condition where blood sugar levels are higher than normal, putting individuals at elevated risk of developing type 2 diabetes. Non-alcoholic fatty liver disease involves an accumulation of excess fat in liver cells, a condition frequently associated with obesity and metabolic dysfunction.
Hormonal mechanisms and liver fat
Scientists said the additional benefit of the ketogenic diet may be explained by specific hormonal changes. The diet led to lower insulin levels and higher glucagon levels, a combination that encourages the liver to reduce its fat stores.
Insulin is a hormone produced by the pancreas that promotes energy storage, while glucagon acts in opposition by signaling the liver to release stored energy when blood sugar levels fall.
A ketogenic diet restricts carbohydrates to shift the body into using fat as its main fuel source. By contrast, the Mediterranean diet emphasizes vegetables, whole grains, and healthy fats such as olive oil, whereas low-fat diets limit overall lipid intake.
Study limitations and further research
Researchers noted that the experiment was limited by its small sample size of 42 participants and its duration of several months. Consequently, it is not yet known whether the health benefits of the diet persist over the long term.
Previous research has also indicated that a ketogenic diet slows down the breakdown of alcohol in the liver and reduces alcohol cravings.
