Urinary Excretion of Select Dietary Polyphenol Metabolites Is Associated with a Lower Risk of Type 2 Diabetes in Proximate but Not Remote Follow-Up in a Prospective Investigation in 2 Cohorts of US Women. Issue 6 (22nd April 2015)

• Record Type: Journal Article
• Authors: Sun, Qi; Wedick, Nicole M; Tworoger, Shelley S; Pan, An; Townsend, Mary K; Cassidy, Aedin; Franke, Adrian A; Rimm, Eric B; Hu, Frank B; van Dam, Rob M
• Is Part Of: Journal of nutrition. Volume 145:Issue 6(2015)
• Page Start: 1280
• Page End: 1288
• Publication Date: 2015-04-22
• Subjects: diabetes -- nutrition -- polyphenol -- urinary biomarker -- women; Nutrition -- Periodicals; Diet -- Periodicals; 613.205
• DOI: 10.3945/jn.114.208736
• Languages: English
• ISSNs: 0022-3166

Abstract

Abstract: Background: Polyphenols are phytochemicals that possess antioxidant and anti-inflammatory properties and improve glucose metabolism in animal experiments, although data from prospective epidemiologic studies examining polyphenol intakes in relation to type 2 diabetes (T2D) risk are inconsistent. Objectives: We examined urinary excretion of select flavonoid and phenolic acid metabolites, as biomarkers of intake, in relation to T2D risk. Methods: Eight polyphenol metabolites (naringenin, hesperetin, quercetin, isorhamnetin, catechin, epicatechin, caffeic acid, and ferulic acid) were quantified in spot urine samples by liquid chromatography/mass spectrometry among 1111 T2D case-control pairs selected from the Nurses' Health Study (NHS) and NHSII. Results: Higher urinary excretion of hesperetin was associated with a lower T2D risk after multivariate adjustment: the OR comparing top vs. bottom quartiles was 0.68 (95% CI: 0.49, 0.96), although a linear trend was lacking ( P = 0.30). The other measured polyphenols were not significantly associated with T2D risk after multivariate adjustment. However, during the early follow-up period [≤4.6 y (median) since urine sample collection], markers of flavanone intakes (naringenin and hesperetin) and flavonol intakes (quercetin and isorhamnetin) were significantly associated with a lower T2D risk. The ORs (95% CIs) comparing extreme quartiles were 0.61 (0.39, 0.98; P -trend: 0.03) for total flavanones and 0.55 (0.33, 0.92; P -trend: 0.04) for total flavonols ( P -interaction with follow-up length: ≤0.04). An inverse association was also observed for caffeic acid during early follow-up only: the OR was 0.52 (95% CI: 0.32, 0.84; P -trend: 0.03). None of these markers was associated with T2D risk during later follow-up. Metabolites of flavan-3-ols and ferulic acid were not associated with T2D risk in either period. Conclusions: These results suggest that specific flavonoid subclasses, including flavanones and flavonols, as well as caffeic acid, are associated with a lower T2D risk in relatively short-term follow-up but not during longer follow-up. Substantial within-person variability of the metabolites in single spot urine samples may limit the ability to capture associations with long-term disease risk.