Abstract
Background: Dietary polyphenols, including flavan-3-ols (F3O), are associated with better health outcomes. The relationship of plasma phenyl-γ-valerolactones (PVLs), the products of colonic bacterial metabolism of F3O, with dietary intakes is unclear. Objectives: To investigate whether plasma PVLs are associated with self-reported intakes of total F3O and procyanidins+(epi)catechins. Design: We measured 9 PVLs by uHPLC-MS-MS in plasma from adults (>60y) in the Trinity-Ulster-Department of Agriculture (TUDA study (2008 to 2012; n=5186) and a follow-up subset (2014 to 2018) with corresponding dietary data (n=557). Dietary (poly)phenols collected by FFQ were analyzed using Phenol-Explorer. Results: Mean (95% confidence interval [CI]) intakes were estimated as 2283 (2213, 2352) mg/d for total (poly)phenols, 674 (648, 701) for total F3O, and 152 (146, 158) for procyanidins+(epi)catechins. Two PVL metabolites were detected in plasma from the majority of participants, 5-(hydroxyphenyl)-γ-VL-sulfate (PVL1) and 5-(4ʹ-hydroxyphenyl)-γ-VL-3ʹ-glucuronide (PVL2). The 7 other PVLs were detectable only in 1-32% of samples. Self-reported intakes (mg/d) of F3O (r = 0.113, P = 0.017) and procyanidin+(epi)catechin (r = 0.122, P = 0.010) showed statistically significant correlations with the sum of PVL1 and PVL 2 (PVL1+2). With increasing intake quartiles (Q1-Q4), mean (95% CI) PVL1+2 increased; from 28.3 (20.8, 35.9) nmol/L in Q1 to 45.2 (37.2, 53.2) nmol/L in Q4; P = 0.025, for dietary F3O, and from 27.4 (19.1, 35.8) nmol/L in Q1 to 46.5 (38.2, 54.9) nmol/L in Q4; P = 0.020, for procyanidins+(epi)catechins. Conclusions: Of 9 PVL metabolites investigated, 2 were detected in most samples and were weakly associated with intakes of total F3O and procyanidins+(epi)catechins. Future controlled feeding studies are required to validate plasma PVLs as biomarkers of these dietary polyphenols.
Original language | English |
---|---|
Pages (from-to) | 476-484 |
Number of pages | 9 |
Journal | The American Journal of Clinical Nutrition |
Volume | 118 |
Issue number | 2 |
Early online date | 10 Jun 2023 |
DOIs | |
Publication status | Published (in print/issue) - 1 Aug 2023 |
Bibliographical note
Funding Information:The VALID Project was awarded under the international Joint Programming Initiative a Healthy Diet for a Healthy Life co-funded ERA-HDHL call on ‘Biomarkers for Nutrition and Health,’ involving partners from the United Kingdom, Italy, and Ireland: Ulster University, Northern Ireland, UK – Biotechnology and Biological Sciences Research Council (Grant BB/P028225/1 ; Prof. Helene McNulty, overall Project Coordinator); University of Parma, Italy—Ministry of Agricultural, Food and Forestry Policies (Grant DM 31967/7303/16 ; Prof. Daniele Del Rio, PI); and Trinity College Dublin, Ireland—Science Foundation Ireland (Grant 16/ERA-HDHL/3361 ; Prof. Anne Molloy, PI).
Publisher Copyright:
© 2023 American Society for Nutrition
Data Access Statement
Data described in the manuscript, code book, and analytic code will be made available upon request, subject to formal application and approval by the TUDA study consortium.Keywords
- Dietary (poly)phenols
- (epi)catechins
- older adults
- phenyl-γ-valerolactones
- flavan-3-ols
- procyanidins