Dietary intake of flavonoid subclasses and risk of type 2 diabetes in prospective cohort studies: A dose–response meta-analysis

Flavonoids intake has been linked to risk of type 2 diabetes theoretically, but the findings were conflicting from observational studies. Results from the recent meta-analysis suggested a moderate favorable effect of total dietary flavonoids consumption on type 2 diabetes risk. However, the relationship, if exists, between total dietary flavonoids consumption and type 2 diabetes risk is unclear, especially further in the association between flavonoid subclasses and risk of type 2 diabetes. Thus, the dose–response relationship was assessed by restricted cubic spline model and multivariate random-effect meta-regression. Among flavonoid subclasses, protective effects were obtained for intakes of flavonols, flavan-3-ols, isoflavones and anthocyanidins in high vs. low analysis and dose–response analysis.