In the news:Fatty Liver Disease, Visual Impact, & Nutritional Factors

Fatty Liver Disease: Prevalence & Visual Impact

Fatty liver disease (now called Metabolic Dysfunction-Associated Steatotic Liver Disease or MASLD), is the most common liver problem in the US. About one quarter of all adults are affected, and rates of MASLD have been steadily rising over the past three decades.

Fatty liver disease is associated with an array of ocular conditions. For example, MASLD may be an independent risk factor for elevated intraocular pressure.span class="footer2">(1) Most recently, MASLD has been linked to a higher incidence of cataract or pseudophakia.span class="footer2">(2)

The first line treatment for MASLD is weight loss through calorie restriction, exercise, and healthy eating. Additionally, researchers continue to assess other nutritional approaches to compliment these lifestyle interventions.

A recent EduFacts issue discussed the results of a meta-analysis which suggests that vitamin E may have some benefit in MASLD. (See SBH.com, Vol. 27, 2023 “Vitamin E Might Help Fight Fatty Liver”). This issue of EduFacts covers new studies pointing to a potential benefit of consuming sufficient dietary niacin and olive oil as well.

Dietary Niacin Tied to Lower Mortality Risk in MASLD

In a prospective cohort studyspan class="footer2">(3) of US adult participants with MASLD, higher intakes of dietary niacin were associated with a reduced risk of all-cause mortality, though there was no apparent connection with CVD mortality risk.

Dietary intake and quality were assessed in 4,315 participants with MASLD in the National Health and Nutrition Examination Survey.

After 8.8 years of follow-up and adjustments for various confounders, the researchers found that the risk of all-cause mortality was 30% lower in participants with the highest niacin intake (equal to or greater than 26.7 mg daily) compared to the lowest intake (equal to or less than 18.4 mg daily).

Sub-group analyses suggest that higher niacin intake may be more strongly associated with lower risk of mortality in patients with MASLD but without diabetes.

The study authors note that “the potential mechanism underlying the association between dietary niacin intake and mortality risk may be partially explained by NAD+ levels. A variety of pathological conditions, such as CVD, obesity, and neurodegenerative diseases, are associated with dysregulation of cellular NAD+ levels.” Further investigation into the relationship of niacin and all-cause and CVD mortality in MASLD is needed.

Could Olive Oil Aid Weight Loss in MASLD?

A body of research has proposed that olive oil, a basic component of the Mediterranean diet with antioxidant and anti-inflammatory properties, may alleviate metabolic disturbances and slow the progression of fatty liver disease.

A new meta-analysisspan class="footer2">(4) of seven randomized controlled trials among people with MASLD found that consuming olive oil (up to about 20 grams or 1 ½ tablespoons daily) as part of the Mediterranean diet or in place of other oils (e.g. canola or safflower) modestly lowered Body Mass Index or BMI. However, olive oil was not shown to lower liver enzymes (ALT, AST) or significantly reduce waist circumference.

While the effects were modest, the overall health benefits of the Mediterranean diet suggest that it may be worth adopting by those with MASLD.

References

1. Jun-Hyuk Lee, et al. Fatty liver Is an independent risk factor for elevated intraocular pressure. Nutrients 14(21): 4455, 2022.
2. Kang HH, et al. Association between cataract and fatty liver diseases from a nationwide cross-sectional study in South Korea. Sci Rep.14: 77, 2024.
3. Ji Pan, et al. Dietary niacin intake and mortality among individuals with nonalcoholic fatty liver disease. JAMA Netw Open. 5;7(2):e2354277, 2024.
4. Tsamos G, et al. The effects of olive oil consumption on biochemical parameters and body mass index of people with nonalcoholic fatty liver dsease: A systematic review and meta-analysis of randomized controlled trials. Nutrients. 16:857, 2024.