Microbiota-Focused Dietary Modulation May Improve MAFLD Management

A new investigation, presented at Digestive Disease Week (DDW) 2024, detailed emerging evidence for diet modulation via the gut-liver axis in a population with metabolic-associated fatty liver disease (MAFLD).¹

Results from the retrospective case-control study revealed the observed microbiota differences between individuals with MAFLD, compared with a control population, were associated with dietary intake and clinical outcomes.
“The finding that diet quality was associated with taxonomic and functional pathway differences is clinically relevant for MAFLD dietary management,” wrote the investigative team, led by Georgina Margaret Williams, PhD, a postdoctoral researcher at The University of Newcastle.

Therapeutic options for MAFLD are limited, but the global burden of MAFLD is rapidly increasing.² Lifestyle changes, including dietary modulation and exercise, are a key component of MAFLD management, with a reduction in energy intake for weight loss marking the first-line therapy for the disease.

Recent findings have highlighted the gut microbiota as a potential therapeutic target to help treat the progression of MAFLD and alleviate some of the health and economic burdens that accompany the disease.³

This retrospective study evaluated the dietary factors related to gut microbiota in MAFLD in order to inform better translational dietary intervention-based research.¹ Participants were recruited from public hospital clinics and an existing related biobank.

For the analysis, the outcomes of interest were the 3-day dietary intake, as well as the clinical markers of MAFLD, and shotgun metagenomic sequencing. These data were transformed for normality and compared using Levene’s t-test and Pearson’s correlation with SPSS.

Overall, Williams and colleagues identified and recruited 29 adults with MAFLD and 29 healthy controls. Compared with the control population, intake of dietary fiber (22.0 ± 11.1g/day versus 29.2 ± 9.2 g/day; P <.01) and omega-3 fatty acids (0.23 ± 0.19 g/day versus 0.76 ± 1.12 g/day; P <.02) were significantly less in the MAFLD group.

In particular, the food group analysis showed the MAFLD cohort consumed fewer high-fiber foods, including whole grains (20.2 ± 19.5 g/day vs. 34.4 ± 27.4 g/day; P <.03) and nuts and seeds (0.35 ± 0.52 g/day versus 1.01 ± 1.48 g/day; P <.03). On the other hand, energy and macronutrient intake demonstrated no differences between the groups.

An examination of the microbiota differences between groups revealed differences across 162 different taxa—approximately 75% were Firmicutes. Williams and colleagues noted the taxa that were significantly less abundant in patients with MAFLD are positively associated with dietary fiber, nuts and seeds, and whole grain intake (P <.05).

The functional pathways (>1200) also significantly differed between groups, according to the analysis, suggesting unique metabolic processes between the patient groups. Significantly elevated functional pathways in the control population were associated with dietary fiber and high-fiber food intake. However, they were negatively correlated with ultra-processed foods and free fructose intake (P <.05).

Inflammatory markers, including high-sensitivity C-reactive protein and cytokeratin 18, were shown to be higher in the MAFLD cohort (P <.03). An increase in inflammation was negatively linked with the total intake of dietary fiber, but positively associated with Blauta spp. These were higher in abundance in patients with MAFLD, compared with the control population (P <.05).

Based on these data, Williams and colleagues indicated the need for further research to focus on the abilities of whole food effects on microbiota and subsequent metabolic outcomes.

“Future translation-focussed research investigating whole food effects on microbiota and subsequent metabolic outcomes is warranted,” investigators wrote.

References

1. _{Williams GM, Hoedt EC, Duncanson K, Talley NJ, Beck EJ. Beyond Calories for Dietary Management in MAFLD: Emerging Evidence for Diet Modulation via the Gut-Liver-Axis. Lecture presented at Digestive Disease Week 2024, May 18 - 21, 2024.}
2. _{Stefano JT, Duarte SMB, Ribeiro Leite Altikes RG, Oliveira CP. Non-pharmacological management options for MAFLD: a practical guide. Ther Adv Endocrinol Metab. 2023;14:20420188231160394. Published 2023 Mar 21. doi:10.1177/20420188231160394}
3. _{Alghamdi W, Mosli M, Alqahtani SA. Gut microbiota in MAFLD: therapeutic and diagnostic implications. Ther Adv Endocrinol Metab. 2024;15:20420188241242937. Published 2024 Apr 15. doi:10.1177/20420188241242937}