Plasma alkylresorcinols, biomarkers of whole-grain intake, are related to lower BMI in older adults

Abstract

Alkylresorcinols (AR) are phenolic lipids found in the bran fraction of whole-grain wheat, rye, and barley. In intervention studies, plasma AR concentration increased in response to greater intakes of whole grain, wheat, and rye. This study examined the cross-sectional associations between plasma AR and habitual whole-grain intake, BMI, and metabolic risk factors in 407 free-living older adults (166 men and 241 women; aged 60-81y; median BMI: 27 kg/m(2)). Plasma AR were measured by liquid chromatography-tandem MS, and whole-grain intakes were estimated by using an FFQ. After adjustment for fasting TG concentrations, median plasma AR concentrations across quartile categories of AR were 5, 14, 27, and 62 nmol/L, respectively. Spearman correlation coefficients between plasma AR and whole-grain wheat-rich foods and total bran intake were 0.31 and 0.27, respectively (both P < 0.0001). After adjustment for multiple covariates, the geometric means of BMI in the lowest and highest quartile category of plasma AR were 27.6 and 26.7 kg/m(2), respectively (P-trend = 0.04). No associations were observed between plasma AR and glucose and insulin. Our study shows a dose-dependent relationship between whole-grain intake and plasma AR and confirms the previously observed inverse relationship between whole-grain intake and BMI using an independent biomarker of whole-grain wheat intake.

Trial registration: ClinicalTrials.gov NCT00183001.

Conflict of interest statement

Author disclosures: J. Ma, A. B. Ross, M. K. Shea, S. J. Bruce, E. Saltzman, A. H. Lichtenstein, and S. L. Booth, no conflicts of interest. A. B. Ross and S. J. Bruce work for the Nestlé Research Center, part of the Nestlé food company that produces a range of whole-grain food products. P. F. Jacques serves on the Bay State Milling Nutrition and Science Advisory Council and the Grains for Health Foundation Scientific Advisory Committee. N. M. McKeown is supported in part by a research-initiated grant from the General Mills Bell Institute of Nutrition and Health and serves a scientific advisor for the Whole Grain Council.

Figures

FIGURE 1

Distribution of plasma alkylresorcinol concentrations in 407 participants. Plasma alkylresorcinol concentration was adjusted for fasting plasma TG by using the residual method for regression analysis.