Adhering to dietary guidelines does not yield flavanol intake levels associated with beneficial cardiovascular effects - Food & Function (RSC Publishing) DOI:10.1039/D6FO00867D<br>View PDF VersionPrevious ArticleNext Article
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This Open Access Article is licensed under a<br>Creative Commons Attribution 3.0 Unported Licence<br>DOI: 10.1039/D6FO00867D<br>(Paper)<br>Food Funct., 2026, 17 , 5715-5725<br>Adhering to dietary guidelines does not yield flavanol intake levels associated with beneficial cardiovascular effects
Javier I.<br>Ottaviani
a,
John W.<br>Erdman<br>Jr.
b,
Francene M.<br>Steinberg
c,
JoAnn E.<br>Manson
de,
Howard D.<br>Sesso
de,
Hagen<br>Schroeter
a and
Gunter G. C.<br>Kuhnle
*f
aMars Food and Nutrition, a segment of Mars, Inc., McLean, VA 22101, USA
bDepartment of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana-Champaign, IL, USA
cDepartment of Nutrition, University of California Davis, Davis, CA 95616, USA
dDivision of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, 900 Commonwealth Ave East, Boston, MA, USA
eDepartment of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA, USA
fDepartment of Food and Nutritional Sciences, University of Reading, Whiteknights, Reading RG6 6AP, UK. E-mail: g.gkuhnle@reading.ac.uk
Received<br>24th February 2026<br>, Accepted 9th May 2026<br>First published on 8th June 2026<br>Abstract<br>Outcomes from the COSMOS trial have reinforced the notion of flavanols as important plant-derived bioactives contributing to cardiovascular health. As discussions continue on whether specific dietary reference values for flavanols are warranted, it is possible that existing dietary guidelines emphasizing fruits and vegetables already yield sufficient flavanol intake levels. If this were the case, developing flavanol specific dietary reference values might be unnecessary. This study therefore aimed at assessing whether adherence to dietary recommendations for fruit and vegetable intake and overall diet quality achieves flavanol intake levels of 500 mg day−1, the amount proven to mediate cardiovascular benefits in the COSMOS trial. Flavanol intake was objectively evaluated using two validated and complementary biomarkers, 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone metabolites (gVLMB) and structurally related (−)-epicatechin metabolites (SREMB), in two geographically distinct studies: COSMOS (US; n = 6509) and EPIC-Norfolk (UK; n = 24154). The results showed that higher fruit and vegetable intakes and diet quality (assessed via the alternative healthy eating index-aHEI) were associated with increased flavanol intake in COSMOS. Nevertheless, fewer than 25% of participants meeting dietary guidelines achieved an estimated flavanol intake of ≥500 mg day−1. Similar findings were observed in EPIC-Norfolk as well as through flavanol intake simulations considering fruits and vegetables commonly consumed in the US diet. In conclusion, adherence to existing dietary guidelines does not yield flavanol intake levels comparable to those shown to provide cardiovascular benefits in COSMOS. Thus, specific dietary reference values for flavanols may still be necessary if aiming to increase the intake of these dietary compounds.
Introduction
Flavanols are a distinct group of plant-derived polyphenolic bioactives.1,2 Evidence from the COSMOS trial, the largest randomized controlled study on polyphenols to date, demonstrated that an intake of 500 mg day−1 of flavanols significantly reduced cardiovascular disease (CVD) mortality by 27% in intention-to-treat analyses, total cardiovascular events by 15% in per-protocol analyses and major cardiovascular events by 16% as a post-hoc endpoint analysed in intention-to-treat analyses in healthy older adults.3 These findings have strengthened the view of flavanols as important dietary compounds for cardiovascular health, which have fuelled ongoing debates on whether specific dietary recommendations for flavanols and other bioactives should be established.4–7 Recently, an expert scientific panel commissioned by the Academy of Nutrition and Dietetics in the United States proposed an intake of 400–600 mg day−1 for cardiometabolic health.8 However, official dietary recommendations for flavanols have not yet been considered. Because fruits and vegetables, including legumes, are major sources of flavanols, and fruits and vegetables are emphasized in current dietary guidelines in the US,9 UK10 and by the World Health Organization,11 it is plausible that adherence to these dietary guidelines could already deliver sufficient flavanol intake levels. Yet no data currently demonstrate whether following recommended intakes of fruits, vegetables, and overall healthy dietary patterns achieves flavanol levels associated with the cardiovascular benefits as shown in COSMOS trial. Addressing this point will provide valuable insights to determine the necessity of developing specific dietary...