Nutrients. 2019;11(3)
Plain language summary
The major established risk factors for non-alcoholic fatty liver disease (NAFLD) include obesity, insulin resistance and dyslipidaemia. This in-depth review looks at research into the effects of macronutrient composition and dietary patterns on NAFLD. Lifestyle modifications leading to weight reduction and/or increased physical activity consistently showed improvements in NAFLD. Based on the reviewed studies, the authors recommend a diet that includes whole grains, mono-unsaturated fatty acids (in moderation), omega 3 poly-unsaturated fatty acids, vegetable protein and fibre, whilst avoiding simple sugars, trans and saturated fats, and red and processed meats. The effects of these macronutrients were independent of weight loss. There was insufficient evidence for a beneficial role of probiotics, resveratrol, coffee, taurine and choline. The Western dietary pattern, characterised by high intakes of saturated fats and fructose, was associated with an increased risk of NAFLD. The Mediterranean Diet (MD), characterised by a high consumption of plant-based foods (whole grains, cereals, seeds, nuts, legumes, vegetables and fruits), moderate consumption of protein-source foods (fish, seafood, and poultry), low to moderate red wine consumption, low consumption of meat, milk and dairy products, was thought to be beneficial. The “Dietary Approach to Stop Hypertension” (DASH) diet, with an emphasis on low intake of sodium, total fat, saturated fat, cholesterol and added sugars, was also found to be beneficial. The effects of low carbohydrate diets were unclear, as any benefits may be due to the associated weight loss rather than the macronutrient composition per se. The authors point out that much of the research is observational (i.e. epidemiological) and that more prospective clinical trials are needed.