Full Breakdown
Healthful Plant-Based Diet Associated with Lower Liver Fat and MASLD Prevalence in Multiethnic Older Adults
6/28/2026, 7:54:57 PM
Background: MASLD and Uncertain Dietary Influences
Metabolic dysfunction-associated steatotic liver disease (MASLD), previously termed non-alcoholic fatty liver disease (NAFLD), is a growing public-health concern for which effective treatments remain limited. While overall diet quality is suspected to affect MASLD risk, the specific impact of plant-based dietary patterns across diverse populations has not been well defined.
Study Overview: Multiethnic Cohort Assessment of Plant-Based Diet Indices
Researchers analyzed cross-sectional data from 1,598 participants aged >= 60 years who were enrolled in the Adiposity Phenotype Study, a sub-study of the Multiethnic Cohort Study. The sample comprised five racial/ethnic groups: Latino, White, African American, Japanese American, and Native Hawaiian. Dietary intake was captured via a food-frequency questionnaire and translated into three established plant-based diet indices:
- Overall Plant-Based Diet Index (PDI) – measures total plant food consumption.
- Healthful Plant-Based Diet Index (hPDI) – emphasizes nutrient-dense plant foods (e.g., nuts, whole grains) and penalizes less-healthy plant items.
- Unhealthful Plant-Based Diet Index (uPDI) – emphasizes refined plant foods and added sugars.
Magnetic resonance imaging quantified hepatic fat, and MASLD cases were identified using standard imaging criteria.
Key Findings: Healthful Plant-Based Diet Linked to Reduced Hepatic Adiposity
- Participants in the highest hPDI quartile exhibited a lower adjusted mean liver-fat percentage (5.39 %) than those in the lowest quartile (6.52 %).
- The odds of MASLD were 42 % lower for the highest versus lowest hPDI quartile (OR = 0.58; 95 % CI = 0.41–0.81).
- The hPDI–MASLD relationship varied significantly by race/ethnicity (p-heterogeneity = 0.001), showing stronger inverse associations among Latino and White participants and weaker associations among African American, Japanese American, and Native Hawaiian participants.
- No consistent associations emerged for the overall PDI or the unhealthful uPDI.
- Within the hPDI, higher nut intake and lower animal-fat consumption were each independently associated with reduced hepatic adiposity.
Data & Statistics Summary
| Metric | Lowest Quartile | Highest Quartile | Effect |
|---|---|---|---|
| Adjusted mean liver fat (%) | 6.52 | 5.39 | ? 1.13 pp |
| MASLD odds ratio (OR) | Reference | 0.58 | 42 % reduction |
| p-value for race/ethnicity interaction | — | — | 0.001 |
Why It Matters: Implications for MASLD Prevention
The study underscores that the quality of plant-based foods—not merely the quantity—correlates with lower liver fat and reduced MASLD prevalence in older adults. The observed ethnic heterogeneity suggests that dietary recommendations may need to be tailored to specific population groups. These findings may inform future dietary strategies aimed at MASLD prevention across heterogeneous communities.
Conflicting Reports & Gaps
- Inconsistent Findings for PDI and uPDI – Neither the overall plant-based index nor the unhealthful plant-based index showed reliable links to liver fat or MASLD, highlighting uncertainty about the role of less-healthful plant foods.
- Ethnic Variation – The strength of the hPDI association differed markedly among racial/ethnic groups, indicating that additional factors (genetic, cultural, or environmental) may modify diet-MASLD relationships.
- Population Scope – The analysis was limited to older adults from five ethnic groups, restricting generalizability to younger populations or other demographic groups.
Collectively, the evidence points to a beneficial role for healthful plant-based diets in mitigating MASLD risk, while also revealing important gaps that warrant further investigation.
