From the Guidelines
A ketogenic diet does not typically predispose to fatty liver disease and may actually help reduce liver fat in some cases, as long as the quality of fats consumed is emphasized, with a focus on healthy fats from sources like avocados, olive oil, nuts, and fatty fish, as suggested by recent studies 1.
Key Considerations
- The ketogenic diet, which is high in fat and very low in carbohydrates, shifts the body's metabolism to use fat as its primary fuel source instead of glucose, potentially decreasing insulin levels and improving insulin sensitivity 1.
- Reducing carbohydrate intake, particularly refined carbs and sugars, can decrease de novo lipogenesis, a major contributor to non-alcoholic fatty liver disease (NAFLD) 1.
- The Mediterranean diet, which is characterized by daily consumption of fresh vegetables, fruit, legumes, minimally processed whole grains, and fish, along with omega-3-fatty acids, such as olive oil, nuts, and seeds, is also beneficial in reducing the risk of NAFLD 1.
- Limiting saturated fatty acid intake, specifically from red and processed meat, and commercially produced fructose consumption, is recommended for adults with NAFLD 1.
Important Factors
- The quality of fats consumed on a keto diet matters significantly, with an emphasis on healthy fats rather than processed or trans fats 1.
- Individuals with existing liver conditions should consult with healthcare providers before starting a ketogenic diet, as certain liver diseases may require specific nutritional approaches 1.
- Recent studies have highlighted the importance of calorie restriction, regardless of dietary composition, and the potential benefits of promoting ketogenesis, potentially achieved via intermittent calorie restriction, in reducing metabolic dysregulation and severity of NAFLD 1.
From the Research
Keto Diet and Fatty Liver
- The relationship between a keto diet and fatty liver is complex, with some studies suggesting that the diet may have beneficial effects on nonalcoholic fatty liver disease (NAFLD) 2, 3, 4.
- A 2020 review of the literature found that the ketogenic diet may have beneficial effects on NAFLD, including improved hepatic pathology and reduced inflammation and fibrosis 2.
- A 2007 pilot study found that a low-carbohydrate, ketogenic diet led to significant weight loss and histologic improvement of fatty liver disease in five patients with obesity-associated fatty liver disease 3.
- Another study published in 2022 reviewed the current evidence on the effects of a ketogenic diet and intermittent fasting on NAFLD, and found that these dietary patterns may have a positive effect on intrahepatic fat content, fibrosis, and liver enzymes 5.
Mechanisms of Action
- The mechanisms by which a keto diet may improve NAFLD are not fully understood, but may involve increased net hydrolysis of intrahepatic triglycerides and partitioning of the resulting fatty acids toward ketogenesis 4.
- A 2020 study found that a ketogenic diet decreased intrahepatic triglycerides by 31% in overweight/obese subjects, despite an increase in nonesterified fatty acids, and attributed this to increased ketogenesis and reduced hepatic insulin resistance 4.
Clinical Implications
- The clinical implications of these findings are that a keto diet may be a useful therapeutic approach for patients with NAFLD, particularly those with obesity and insulin resistance 2, 3, 4.
- However, more research is needed to fully understand the effects of a keto diet on NAFLD and to determine the optimal dietary approach for patients with this condition 5, 6.