Nonalcoholic fatty liver disease (NAFLD) is becoming a global epidemic. Being the most common cause of chronic liver disease worldwide, it affects approximately 25% of the adult population. NAFLD is defined as the accumulation of fat in the liver in people who do not consume excessive amounts of alcohol. It is closely associated with obesity, with a prevalence as high as 90% in morbidly obese individuals. Approximately 25% of patients with NAFLD have nonalcoholic steatohepatitis (NASH), which is associated with a 20% risk of progression to liver cirrhosis; the gradual replacement of normal liver tissue by scar tissue.
Diet and nutrient intake is linked to NAFLD but data from clinical trials are sparse. This review looked at the pathophysiology behind how specific macronutrient components (quality of proteins, carbohydrates (CHOs), and fats) and which eating patterns can either promote or reverse NAFLD.
A high-calorie diet is fundamentally linked to obesity and is the initial trigger point for NAFLD through adipose tissue expansion, increased inflammation and mitochondrial dysfunction. Emerging data suggests that calorie restriction to achieve weight loss of >10% overall body weight is an extremely effective lifestyle intervention for both the prevention of NAFLD and improvement of NAFLD-symptoms.
Increasing fiber intake by increasing intake of fruits, vegetables, whole grains and legumes, should be encouraged in patients with NAFLD. Furthermore, the data supports replacing saturated fat with unsaturated fats, reducing intake of refined carbohydrates, and increasing the consumption of plant-based foods in the diet
Prospective trials comparing various diets are limited by lack of sufficient power or data, and therefore no specific diet is recommended at this time. However diets that incorporate the above recommendations include plant-based diets such as the Dietary Approaches to Stop Hypertension (DASH), Mediterranean, vegetarian, and vegan diets.
Reference: Hydes et al. https://www.e-cmh.org/journal/view.php?doi=10.3350/cmh.2020.0067