Associations Between Dietary Fiber and Inflammation, Hepatic Function, and Risk of Type 2 Diabetes in Older Men: Potential mechanisms for the benefits of fiber on diabetes risk

OBJECTIVE: To examine the relationship between dietary fiber and the risk of type 2 diabetes in older men and the role of hepatic and inflammatory markers. RESEARCH DESIGN AND METHODS: The study was performed prospectively and included 3,428 nondiabetic men (age 60–79 years) followed up for 7 years, during which there were 162 incident cases of type 2 diabetes. RESULTS: Low total dietary fiber (lowest quartile ≤20 g/day) was associated with increased risk of diabetes after adjustment for total calorie intake and potential confounders (relative risk −1.47 [95% CI 1.03–2.11]). This increased risk was seen separately for both low cereal and low vegetable fiber intake. Dietary fiber was inversely associated with inflammatory markers (C-reactive protein, interleukin-6) and with tissue plasminogen activator and γ-glutamyl transferase. Adjustment for these markers attenuated the increased risk (1.28 [0.88–1.86]). CONCLUSIONS: Dietary fiber is associated with reduced diabetes risk, which may be partly explained by inflammatory markers and hepatic fat deposition.