Role of Fasting in the Management of Non-alcoholic Fatty Liver Disease (NAFLD): A Systematic Review of Clinical Trials

TL;DR

This review shows that fasting methods like time-restricted feeding and alternate-day fasting can improve liver health and metabolism in people with non-alcoholic fatty liver disease.

Contribution

The study systematically evaluates the effectiveness of various fasting protocols for managing NAFLD through clinical trials.

Findings

Fasting protocols reduced hepatic steatosis and improved insulin sensitivity.

TRF and ADF were well tolerated and effective when combined with exercise or low-sugar diets.

Study limitations include inconsistent protocols, small sample sizes, and short follow-up periods.

Abstract

Non-alcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver disease. Lifestyle changes, especially dietary, have been recognized as important measures for managing the condition. This systematic review aimed at assessing the effectiveness of fasting protocols, including time-restricted feeding (TRF), alternate-day fasting (ADF), the 5:2 diet, and other lifestyle interventions in enhancing metabolic and hepatic profiles. The search for randomized controlled trials (RCTs) was extended to include PubMed, Scopus, ScienceDirect, and Google Scholar for articles published between 2019 and 2024. The studies that included participants with fatty liver disease and examined the effects of fasting on hepatic steatosis, metabolic markers, and liver enzymes were included, and the quality of the studies was evaluated using the Cochrane risk of bias tool. Out of the 12 RCTs that were included in the study, there was a significant reduction in hepatic steatosis, an increase in insulin sensitivity, and a decrease in inflammatory markers. TRF and ADF were found to be effective forms of calorie restriction, as they were well tolerated by the patients. The combination of ADF with aerobic exercise and TRF with low-sugar diets was seen to have potent effects on the liver and other metabolic parameters. However, certain drawbacks include the variation in the fasting protocols, small subject numbers, and brief follow-up periods. The current study highlights that intermittent fasting is a viable non-pharmacological option for the management of NAFLD with a focus on the timing and content of eating periods. The following are needed to strengthen the evidence and to guide the clinicians in its application: standardized fasting protocols and long-term trials.

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