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ARS Home » Northeast Area » Beltsville, Maryland (BHNRC) » Beltsville Human Nutrition Research Center » Food Components and Health Laboratory » Research » Publications at this Location » Publication #347068

Research Project: Absorption, Metabolism, and Health Impacts of Bioactive Food Components

Location: Food Components and Health Laboratory

Title: Dietary intakes of flavan-3-ols and cardiovascular health: a field synopsis using evidence mapping of randomized trials and prospective cohort studies

Author
item Raman, Gowri - Tufts University
item Shams-white, Marissa - Tufts University
item Avendano, Esther - Tufts University
item Chen, Fan - Tufts University
item Novotny, Janet
item Cassidy, Aedin - University Of East Anglia

Submitted to: Systematic Reviews
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/26/2018
Publication Date: 7/18/2018
Citation: Raman, G., Shams-White, M., Avendano, E., Chen, F., Novotny, J., Cassidy, A. 2018. Dietary intakes of flavan-3-ols and cardiovascular health: a field synopsis using evidence mapping of randomized trials and prospective cohort studies. Systematic Reviews. 7. https://doi.org/10.1186/s13643-018-0764-z.
DOI: https://doi.org/10.1186/s13643-018-0764-z

Interpretive Summary: There is considerable interest in the impact of increased flavan-3-ol intake on cardiovascular disease (CVD) and diabetes outcomes, and hundreds of scientific studies have been conducted to develop understanding of the relationships. We used a method called qualitative gap analysis, to determine the extent of the evidence base to initiate a future systematic review investigating the impact of flavan-3-ol intake on CVD and diabetes outcomes. We developed a research protocol, convened a technical expert panel to refine the specific research questions, conducted a systematic search in multiple databases, double-screened abstracts and full-text articles, performed data extractions, and synthesized the data. Through a systematic, evidence-based approach, evidence mapping on flavan-3-ol intake and CVD outcomes allowed us to understand the distribution of the current evidence as well as to identify evidence gaps. These data highlight the need for a full systematic review and identify the research need to conduct further long-term clinical trials. These results will be used by scientists.

Technical Abstract: There is considerable interest in the impact of increased flavan-3-ol intake on cardiovascular disease(CVD) and diabetes outcomes. Through evidence mapping, we determined the extent of the evidence base toinitiate a future systematic review investigating the impact of flavan-3-ol intake on CVD and diabetes outcomes. We developed a research protocol, convened a technical expert panel (TEP) to refine the specificresearch questions, conducted a systematic search in multiple databases, double-screened abstracts and full-textarticles, performed data extractions, and synthesized the data. We focused on randomized controlled trials (RCTs)and prospective cohort studies which assessed intakes of flavan-3-ol from foods, beverages, and supplement/extractsources on biomarkers and clinical outcomes of CVD and diabetes. Of 257 eligible articles, 223 and 34 publications contributed to 226 RCTs and 39 prospective cohort studies,respectively. In RCTs, the most frequently studied interventions were cocoa-based products (23.2%); berries (16.1%); teain the form of green tea (13.9%), black tea (7.2%), or unspecified tea (3.6%); and red wine (11.2%). Mean total flavan-3-olintake was highest in the cocoa-based trials (618.7 mg/day) and lowest in the interventions feeding red wine (123.7 mg/day). The most frequently reported outcomes were intermediate biomarkers including serum lipid levels (63.4%),blood glucose (50.9%), blood pressure (50.8%), flow-mediated dilation (21.9%), and high-sensitivity C-reactive protein(21.9%). The included 34 prospective cohort studies predominantly examined exposures to flavan-3-ols (26%),cocoa-based products (23.2%), berries (16.1%), and green tea (13.9%) and CVD incidence and mortality. Through a systematic, evidence-based approach, evidence mapping on flavan-3-ol intake and CVDoutcomes demonstrated sufficient data relating to flavan-3ol intake and biomarkers and clinical outcomes of CVD anddiabetes. The current evidence base highlights the distribution of available data which both support the developmentof a future systematic review and identified the research need for future long-term RCT