Non-alcoholic fatty liver disease (NAFLD) has become a growing concern, affecting around 30% of adult Americans, leading researchers to explore potential preventive measures. A recent cross-sectional study, drawing data from the National Health and Nutrition Examination Survey (NHANES), sheds light on the possible impact of dietary carotenoids, particularly provitamin A carotenoids, on the risk of developing NAFLD.
NAFLD encompasses various liver ailments, ranging from simple steatosis to more severe conditions like non-alcoholic steatohepatitis (NASH), cirrhosis, and hepatocellular carcinoma (HCC). Unlike alcoholic liver diseases, NAFLD is associated with the accumulation of lipids in the liver, independent of excessive alcohol consumption.
The study, consisting of 6,613 participants aged around 51 years, explored dietary vitamin A intake and its sources in relation to NAFLD risk. Participants were found to consume approximately 334 μg/1000 kcal/day of vitamin A from their diet. Notably, 36.7% of the cohort was diagnosed with NAFLD.
While the majority of NAFLD patients were associated with higher preformed vitamin A consumption, the study found no significant link between total dietary vitamin A intake and NAFLD risk after adjusting for potential confounders. However, a noteworthy inverse correlation emerged between provitamin A carotenoid consumption and NAFLD risk, irrespective of age and gender.
The study revealed a linear negative dose-response relationship between provitamin A carotenoid consumption and NAFLD risk, suggesting a potential protective effect. These findings align with previous studies highlighting carotenoids’ ability to counteract inflammation, steatosis, and fibrosis progression in more severe cases of NAFLD, such as NASH.
Carotenoids, known for their antioxidant properties, have been shown to influence adiponectin expression, contributing to the downregulation of nuclear factor-kappa B (NFκB) and TNF-α, which are linked to increased NAFLD risk. As there is currently no approved drug for NAFLD treatment, the study suggests that dietary intervention, particularly the consumption of provitamin A carotenoids, could play a role in reducing the risk of developing NAFLD.
While the study offers promising insights, it acknowledges potential contradictions in previous research due to factors such as the lack of adjustment for confounders and inconsistencies in dietary patterns, study design, and ethnic backgrounds. As research continues, dietary considerations, specifically the inclusion of provitamin A carotenoids, may emerge as a practical strategy for those looking to address or prevent NAFLD.