Systematic Reviews
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World J Hepatol. Mar 27, 2025; 17(3): 102286
Published online Mar 27, 2025. doi: 10.4254/wjh.v17.i3.102286
Metabolic dysfunction-associated steatotic liver disease and omega-6 polyunsaturated fatty acids: Friends or foes
Mona A Hegazy, Safaa M Ahmed, Shaimaa M Sultan, Osama F Afifi, Manal A Mohamed, Alshimaa E Azab, Mohamed A Hassanen, Rakan K Zaben
Mona A Hegazy, Department of Internal Medicine, Kasr Aliny Hospital, Faculty of Medicine, Cairo University, Cairo 12556, Egypt
Safaa M Ahmed, Department of Neonatology, Mounira General Hospital, Cairo 4262130, Egypt
Shaimaa M Sultan, Department of Maternal and Pediatric Health, Shubra Elkhema Medical Administration, Qalyubia 13768, Egypt
Osama F Afifi, Department of Neonatology, Ashmoun Hospital, Menofia 32811, Egypt
Manal A Mohamed, Department of Internal Medicine, Elnasr Hospital, Helwan 11731, Egypt
Alshimaa E Azab, Department of Anesthesia, Al Helal Insurance Hospital, Qism Shebin 32514, Egypt
Mohamed A Hassanen, Rakan K Zaben, Department of Clinical Nutrition, Egyptian Fellowship, Cairo 11559, Egypt
Author contributions: Hegazy MA conceptualized the study, designed the research framework, critically reviewed the overarching concept and structure, and contributed to both the manuscript drafting and final revision; Ahmed SM, Sultan SM, Afifi OF, Mohamed MA, Azab AE, Hassanen MA, and Zaben RK collectively participated in the systematic screening of citations from full-text articles, data collection, and the comprehensive review of the manuscript, contributing equally to its preparation; and all authors have confirmed their approval of the finalized manuscript for publication.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Mona A Hegazy, MD, Professor, Department of Internal Medicine, Kasr Aliny Hospital, Faculty of Medicine, Cairo University, Kasr Alainy Street, Garden City, Cairo 12556, Egypt. monahegazy@cu.edu.eg
Received: October 13, 2024
Revised: February 20, 2025
Accepted: March 5, 2025
Published online: March 27, 2025
Processing time: 163 Days and 9.8 Hours
Abstract
BACKGROUND

Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease worldwide. Its prevalence is closely linked to the dramatic rise in obesity and non-communicable diseases. MASLD exhibits a progressive trajectory that may culminate in development of hepatic cirrhosis, thereby predisposing affected individuals to an elevated likelihood of hepatocarcinogenesis. Diet, especially dietary fatty acids, serves as a key link between nutrient intake and MASLD pathogenesis.

AIM

To explore the impact of various omega-6 fatty acid subtypes on the pathogenesis and therapeutic strategies of MASLD.

METHODS

A systematic literature search was conducted across Web of Science, PubMed, Cochrane Central, Scopus, and Embase databases from inception through June 2024 to identify all original studies linking different subtypes of omega-6 polyunsaturated fatty acids to the pathogenesis and management of MASLD. The search strategy explored the linkage between omega-6 polyunsaturated fatty acids and their subtypes, including linoleic acid (LA), gamma-linolenic acid (GLA), arachidonic acid, conjugated LA, and docosapentaenoic acid, in relation to MASLD and cardiometabolic risk.

RESULTS

By employing the specified search strategy, a total of 83 articles were identified as potentially eligible. During the title, abstract, and full-text screening phases, 27 duplicate records were removed, leaving 56 records for relevance screening. Of these, 43 records were excluded for reasons such as irrelevance and language restrictions (limited to English), resulting in 13 full-text articles being included for detailed assessment (10 human studies,1 animal study, and 2 review articles). Although certain subtypes, as GLA, dihomo-GLA, omega-6-derived oxylipins, and most arachidonic acid-derived eicosanoids, exhibit pro-inflammatory effects, our findings suggest that other subtypes such as LA, cis-9, trans-11 conjugated LA, and docosapentaenoic acid have beneficial effects on fatty liver, cardiometabolic risk factors, and inflammation, even at high intake levels.

CONCLUSION

The varying health effects of omega-6 fatty acids, ranging from anti-inflammatory to pro-inflammatory impacts on the liver, leave the question of their recommendation for MASLD patients unresolved. This underscores the importance of careful selection when considering omega-6 supplementation.

Keywords: Metabolic dysfunction-associated steatotic liver disease; Omega-6 polyunsaturated fatty acids; Conjugated linoleic acid; Arachidonic acid; Lipid metabolism; Oxidative stress; Steatohepatitis; Eicosanoids

Core Tip: Dietary habits extend beyond influencing metabolic dysfunction-associated steatotic liver disease onset, serving as a fundamental component in its therapeutic management. While fats have a deleterious role in the pathogenesis of liver steatosis and fibrosis, unsaturated fats provide a crucial safeguard in metabolic dysfunction-associated steatotic liver disease management. Omega-6 polyunsaturated fat subtypes exhibit varying pro- and anti-inflammatory effects; most arachidonic acid-derived eicosanoids, exhibit pro-inflammatory effects, while linoleic acid and natural conjugated linoleic acid do not increase inflammation, even at high doses, and may even exert beneficial effects. Therefore, further research is needed to explore dietary sources of healthy omega-6 fatty acids.