Objectives: Irregular or late eating patterns may increase the risk of non-alcoholic fatty liver disease (NAFLD), the most common hepatic disorder worldwide, by disrupting the circadian rhythm involved in lipid metabolism and insulin sensitivity. However, there have been few studies that examined the role of meal timing in NAFLD risk. Therefore, the present study aimed to investigate the association between meal frequency and timing and the risk of NAFLD in a representative sample of Korean adults.
Methods: In this large cross-sectional analysis of 53,219 adults in the Korea National Health and Nutrition Examination Survey, eating episodes, meal timing, and meal-specific (breakfast, lunch, and dinner) timing and energy composition were estimated using dietary and meal timing data collected via a 24-hour recall. NAFLD was defined by a hepatic steatosis index >36. Multivariable-adjusted odds ratios (MVOR) and 95% confidence intervals (CI) were used to examine the associations between the meal timing and NAFLD risk.
Results: While the frequency of daily eating episodes had no association with NAFLD risk, late eaters who had their first meal in the afternoon had a significantly increased risk of NAFLD (MVOR [95%CI] First meal timing ≥ 2:27 pm (the median time between the first and the last eating episodes) vs < 2:27 pm: 1.11 [1.03-1.19]), compared to early eaters. This positive association with late eating was more evident in men (MVOR [95%CI]: 1.14 [1.03-1.27]) than women (P-interaction ≤ 0.013). Moreover, in meal-specific analyses, there was a significant increased risk of NAFLD with late breakfast (MVOR [95% CI] Having breakfast after 9am vs. before 8am: 1.18 [1.09-1.28], P-trend≤0.001) and lower risk with energy consumption during breakfast (MVOR [95% CI]≥25% energy intake vs. none during breakfast: 0.89 [0.81-0.97], P-trend: 0.004). No associations were observed with lunch- and dinner-specific meal timing or energy composition.
Conclusions: Our results suggest that the late eating, particularly irregular breakfast consumption, may elevate the risk of NAFLD. Large cohort studies are warranted to replicate our findings.
Funding Sources: The Ministry of Education and National Research Foundation of Korea and Ewha Womans University supported this research.
