Effect of a Low-Calorie Dietary Intervention on Liver Health and Body Weight in Adults with Metabolic-Dysfunction Associated Steatotic Liver Disease (MASLD) and Overweight/Obesity: A Systematic Review and Meta-Analysis.

Sarah J Nevitt, Theresa J Hydes, Laurence J Dobbie, Jamie Burgess, Daniel J Cuthbertson, Uazman Alam, Azlinda Hamid

Journal: Nutrients 2024;16(7):

PMID: 38613063

Plain Language Summary

Metabolic dysfunction associated steatotic liver disease (MASLD) is associated with being overweight. Low calorie diets (LCD) have been shown to reduce body weight and may be of benefit to individuals with MASLD. This systematic review and meta-analysis examined how a LCD affects liver health and body weight in adults with MASLD and obesity.

The results included 15 studies that focused on randomised controlled trials and cohort studies. They show that participants on a low-calorie diet lost an average of 9.1 kg compared to those not on the diet. However, the diet did not significantly lower levels of a liver enzyme called alanine transaminase (ALT) and liver fat content, which are often used to assess liver health. Some specific types of low-calorie diets, like the Mediterranean-LCD, did show a reduction in ALT levels and liver stiffness over longer periods. Additionally, a Green-Mediterranean-LCD was effective in reducing liver fat, regardless of body weight changes.

The study concluded that people with MASLD and obesity on a LCD may improve their liver health. This study could be used by healthcare professionals to understand that weight loss is important for liver health and there are several types of eating patterns that can achieve this.

Abstract

INTRODUCTION

Metabolic-dysfunction Associated Steatotic Liver Disease (MASLD) is a common cause of chronic liver disease. This review assessed the efficacy of a Low-Calorie Diet (LCD) on liver health and body weight in people living with MASLD and obesity.

METHODS

The study was registered with PROSPERO (CRD42021296501), and a literature search was conducted using multiple databases. The key inclusion criteria were randomised controlled trials or cohort studies, obesity/overweight and MASLD. Two authors screened abstracts, reviewed full texts and performed data extraction and quality assessment. The primary outcome was the change in the serum ALT, and secondary outcomes included the changes in the serum AST, intrahepatic lipid content (IHL), quantified non-invasively via MRI/MRS, and body weight.

RESULTS

Fifteen studies were included. The LCD reduced body weight by 9.1 kg versus the control (95%CI: -12.4, -5.8) but not serum ALT (-5.9 IU/L, -13.9, 2.0). Total Dietary Replacement (TDR) reduced IHL by -9.1% vs. the control (-15.6%, -2.6%). The Mediterranean-LCD for ≥12 months reduced ALT (-4.1 IU/L, -7.6, -0.5) and for 24 months reduced liver stiffness versus other LCDs. The Green-Mediterranean-LCD reduced IHL, independent of body weight. Limited studies assessed those of Black or Asian ethnicity, and there was heterogeneity in the methods assessing the liver fat content and fibrosis.

CONCLUSIONS

In people with MASLD and obesity, an LCD intervention reduces IHL and body weight. Trials should focus on the recruitment of Black and Asian ethnicity participants.

Address: Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L9 7AL, UK.; Department of Diabetes & Endocrinology, Guys Hospital, Guy's and St Thomas' NHS Foundation Trust, London SE1 9RT, UK.; Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L9 7AL, UK.; University Hospital Aintree, Liverpool University Hospitals NHS Foundation Trust, Liverpool L9 7AL, UK.; Department of Cardiovascular and Metabolic Medicine, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L9 7AL, UK.; Department of Health Data Science, Institute of Population Health, University of Liverpool, Liverpool L3 5TR, UK.; Centre for Reviews and Dissemination, University of York, York YO10 5DD, UK.

DOI: 10.3390/nu16071030