Lifestyle interventions for the treatment of non-alcoholic fatty liver disease in adults: A systematic review

Abstract

Non-alcoholic fatty liver disease is a serious and growing clinical problem. Despite lifestyle modification, i.e. diet and physical activity, being the recommended therapy, there are currently no systematic evaluations of its efficacy. This review applies a systematic approach to evaluating lifestyle modifications studied to date. Medline (Pubmed), Scopus, and the Cochrane Controlled Trials Register were searched for studies and study groups assessing the effect of diet, physical activity, and/or exercise modification in adult populations with non-alcoholic fatty liver disease. The outcome markers of interest were indicators of steatosis, histological evidence of inflammation and fibrosis, and glucose control/insulin sensitivity. We identified 23 studies for inclusion; seven had control groups, but only six were randomised. Eleven groups received diet-only interventions, two exercise-only, and 19 diet and physical activity/exercise. Studies consistently showed reductions in liver fat and/or liver aminotransferase concentration, with the strongest correlation being with weight reduction. Of the 5 studies reporting changes in histopathology, all showed a trend towards reduction in inflammation, in 2 this was statistically significant. Changes in fibrosis were less consistent with only one study showing a significant reduction. The majority of studies also reported improvements in glucose control/insulin sensitivity following intervention. However, study design, definition of disease, assessment methods, and interventions varied considerably across studies. Lifestyle modifications leading to weight reduction and/or increased physical activity consistently reduced liver fat and improved glucose control/insulin sensitivity. Limited data also suggest that lifestyle interventions may hold benefits for histopathology.

Intermittent calorie restriction largely counteracts the adverse health effects of a moderate‐fat diet in aging C57BL/6J mice

“…CR interventions are often applied to achieve weight loss in overweight and obese subjects 75, 76, 77. In the second part of our study, we explored into what extent, the molecular effects induced by a MF diet in the liver during the first 12 months of life, can be reversed by exposure to the INT diet during the second 12 months of life.…”

“…First, in our obesogenic society, where about half of the population is overweight or obese 1, maintaining a reduced energy intake is the best nutritional strategy to achieve and maintain weight loss 2, 3. Since obesity causes a wide range of serious chronic diseases, the negative energy balance induced by a CR diet will result in weight loss and induce, concomitantly, health promoting effects.…”

EASL–EASD–EASO Clinical Practice Guidelines for the management of non-alcoholic fatty liver disease

“…Adherence to the Mediterranean diet has been reported to reduce liver fat on 1 H-MRS, when compared with a low fat/ high carbohydrate diet in a crossover comparison [110,111].…”

“…• 150-200 min/week of moderate-intensity aerobic physical activities in 3-5 sessions are generally preferred (brisk walking, stationary cycling) • Resistance training is also effective and promotes musculoskeletal fitness, with effects on metabolic risk factors • High rates of inactivity-promoting fatigue and daytime sleepiness reduce compliance with exercise Physical activity follows a dose-effect relationship and vigorous (running) rather than moderate exercise (brisk walking) carries the full benefit, including for NASH and fibrosis [110,117,118] Any engagement in physical activity or increase over previous levels is however better than continuing inactivity.…”

Gamma glutamyltransferase and risk of future dementia in middle‐aged to older Finnish men: A new prospective cohort study

“…Individuals with elevated GGT levels might benefit from nutritional and lifestyle modification (e.g., weight loss and physical activity [33]) that decrease GGT levels. Our findings are among the first in this research area and therefore is a topic for further investigation.…”