Sugar-sweetened beverages, low/no-calorie beverages, fruit juice and non-alcoholic fatty liver disease defined by fatty liver index: the SWEET project

Background: Sweetened beverage intake may play a role in non-alcoholic fatty liver disease (NAFLD) development, but scientific evidence on their role is limited. This study examined associations between sugar-sweetened beverages (SSB), low/no-calorie beverages (LNCB) and fruit juice (FJ) intakes and NAFLD in four European studies.

Methods: Data for 42,024 participants of Lifelines Cohort, NQPlus, PREDIMED-Plus and Alpha Omega Cohort were cross-sectionally analysed. NAFLD was assessed using Fatty Liver Index (FLI) (≥60). Restricted cubic spline analyses were used to visualize dose-response associations in Lifelines Cohort. Cox proportional hazard regression analyses with robust variance were performed for associations in individual cohorts; data were pooled using random effects meta-analysis. Models were adjusted for demographic, lifestyle, and other dietary factors.

Results: Each additional serving of SSB per day was associated with a 7% higher FLI-defined NAFLD prevalence (95%CI 1.03-1.11). For LNCB, restricted cubic spline analysis showed a nonlinear association with FLI-defined NAFLD, with the association getting stronger when consuming ≤1 serving/day and levelling off at higher intake levels. Pooled Cox analysis showed that intake of >2 LNCB servings/week was positively associated with FLI-defined NAFLD (PR 1.38, 95% CI 1.15-1.61; reference: non-consumers). An inverse association was observed for FJ intake of ≤2 servings/week (PR 0.92, 95% CI: 0.88-0.97; reference: non-consumers), but not at higher intake levels. Theoretical replacement of SSB with FJ showed no significant association with FLI-defined NAFLD prevalence (PR 0.97, 95% CI 0.95-1.00), whereas an adverse association was observed when SSB was replaced with LNCB (PR 1.12, 95% CI 1.03-1.21).

Conclusions: Pooling results of this study showed that SSB and LNCB were positively associated with FLI-defined NAFLD prevalence. Theoretical replacement of SSB with LNCB was associated with higher FLI-defined NAFLD prevalence. An inverse association was observed between moderate intake of FJ and FLI-defined NAFLD. Our results should be interpreted with caution as reverse causality cannot be ruled out.