Background: In order to attenuate the measurement error inherent in dietary recall methods, alkylresorcinols (ARs) have been proposed as a biomarker of whole-grain (WG) intake. Although ARs have shown promise in experimental and observational studies, most of this research has been conducted in Nordic populations that consume relatively high amounts of WG.
Objectives: The objectives of this study were to assess the utility of plasma AR concentration as a WG intake biomarker and identify the primary dietary and non-dietary determinants of plasma AR concentration in a population that consumes relatively few WG.
Methods: This ancillary study used data from first-year college students (n=122) who completed three interviewer-administered 24-hour recalls and had two fasting venous blood draws performed on non-consecutive days. Dietary data was compiled using the Nutrition Data System for Research. Blood lipids and glucose were determined via enzymatic assay and plasma AR concentrations were determined by gas chromatography-mass spectrometry. Correlation coefficients were calculated between plasma AR concentrations and dietary intake variables and cardiometabolic risk factors. One-way ANOVA and Tukey’s post-hoc test were used to assess group differences across plasma AR quartiles. Determinants of plasma AR concentration were assessed using multiple regression models. Statistical analyses were performed using R version 3.2.3.
Results: Plasma AR concentration was significantly positively correlated with WG intake (rs = 0.24, p <0.01). The correlation was stronger in males (n=36, rs = 0.33, p < 0.05) than females (n=86, rs = 0.18, p = 0.08). One-way ANOVA across plasma AR quartiles was significant for fiber intake [F(3,118) = 8.58, p < 0.001] and Tukey’s HSD test showed that the mean daily fiber intake for the highest AR quartile was significantly greater than for the lowest (M = 20.2 ± 1.9 g, 14.7 ± 1.4 g respectively). The only cardiometabolic risk factor that was significantly associated with plasma AR concentration was triglycerides (rs = 0.27, p < 0.01). Multiple regression models including log-transformed dietary variables showed that WG bread was the only significant food-item predictor of plasma AR concentration (β = 0.54, p < 0.01).
Conclusions: Although plasma AR concentration was significantly associated with WG and fiber intake, triglycerides were the primary determinant and the relationships were not strong enough to produce accurate WG intake prediction models. More research is needed on the use of AR as a quantitative biomarker in low WG-consuming populations.
|Advisor:||Lofgren, Ingrid E.|
|Commitee:||English, Cathy, Slitt, Angela|
|School:||University of Rhode Island|
|Department:||Nutrition and Food Sciences|
|School Location:||United States -- Rhode Island|
|Source:||MAI 55/04M(E), Masters Abstracts International|
|Keywords:||Alkylresorcinol, Biomarker, Nutrition, Rye, Wheat, Whole-grain|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be