Abstract 4367196: Intake of Fiber From Different Food Sources and Type 2 Diabetes Risk: An Integrated Analysis of Epidemiological and Multi-Omics Data

Background: Dietary fiber intake has been associated with a lower risk of type 2 diabetes (T2D). However, the association between fiber from various food sources and T2D risk remains underexplored, and the mechanisms involved are not yet well understood. Methods: We followed 155,633 women and 42,528 men from three large prospective US cohorts for up to 34 years. Dietary fiber intake was estimated using validated food-frequency questionnaires. Cox proportional hazards models were used to evaluate the association between fiber intake and T2D risk. We examined the association between fiber intake, ten plasma metabolic biomarkers, and a metabolomic score indicative of T2D risk. Additionally, we assessed the association between fiber intake, the gut microbiome, and the T2D metabolomic score. Results: During follow-up, we documented 18,681 incident T2D cases. A higher intake of total fiber (HR comparing extreme quintiles=0.89; 95% CI: 0.84, 0.95), cereal fiber (HR=0.77; 95% CI: 0.73, 0.82), and fruit fiber (HR=0.88; 95% CI: 0.83, 0.93) was associated with a lower T2D risk (all P-trend≤0.004). In contrast, fiber from vegetables, particularly starchy vegetables (peas, yams/sweet potatoes, and corn) and onions, was associated with a moderately increased risk of T2D. Total fiber, cereal fiber, and fruit fiber were associated with more favorable profiles of plasma insulinemic, lipid, and inflammatory biomarkers, and a metabolomic profile indicative of a lower T2D risk. We also identified multiple gut microbial species, such as Faecalibacterium prausnitzii, Ruminococcus lactaris , and Gemmiger formicilis , along with relevant butyric acid-producing enzymes, all of which were associated with fruit fiber intake and may play a role in the relationship between fiber intake and T2D. Conclusion: A higher intake of total, cereal, and fruit fiber is associated with a reduced risk of T2D and more favorable metabolic profiles, with the gut microbiome potentially contributing to the beneficial association of fruit fiber.