Most People Are Missing the Heart-Protecting Nutrient Hidden in These Foods
New research finds fewer than 20% of people get enough flavanols — compounds that cut cardiovascular death risk — even eating 5 daily servings of produce.
Summary
A large international study involving over 30,000 people found that fewer than one in five adults consume enough flavanols, natural plant compounds linked to significantly reduced cardiovascular disease risk. The research, led by University of Reading scientists alongside Harvard Medical School and UC Davis, shows that simply eating five daily servings of fruits and vegetables is not enough — the specific foods chosen matter far more. Flavanol-rich options like plums, blackberries, cranberries, broad beans, cherries, apples, and green tea can dramatically boost intake. The COSMOS trial previously established that 500mg of flavanols daily lowers heart disease death risk, but most people consuming standard healthy diets fall well below that threshold.
Detailed Summary
Most people who believe they are eating a heart-healthy diet may be falling short on a critical class of compounds called flavanols. New research published in Food and Function on June 8, 2026, reveals that fewer than 20% of adults in the UK and US consume enough of these plant-based nutrients to gain meaningful cardiovascular protection — even among those following standard dietary guidelines.
The international study, led by the University of Reading in collaboration with Harvard Medical School, UC Davis, and Mars, Inc., analyzed dietary data from over 30,000 individuals. Researchers used biomarker measurements — a more objective tool than typical food questionnaires — to assess actual flavanol intake. Their findings show that meeting the general recommendation of five daily fruit and vegetable servings does not guarantee adequate flavanol consumption.
The target intake, informed by the landmark COSMOS clinical trial, is approximately 500mg of flavanols per day — an amount associated with significantly reduced cardiovascular mortality. The new data suggest most people remain well below this level. The richest sources per serving include plums (~450mg per punnet), cranberries (~300mg), blackberries (~250mg), one cup of green tea (~200mg), broad beans (~140mg), and a medium apple with skin (~110mg).
Lead author Dr. Javier Ottaviani emphasized that food choice — not food volume — is the key variable. A handful of blackberries or a daily cup of green tea could meaningfully shift flavanol status and potentially cardiovascular risk over time.
Caveats apply: the study includes industry co-authorship (Mars, Inc.), which warrants scrutiny given commercial interests in cocoa-derived flavanols. Additionally, while associations are strong, dietary biomarker studies cannot fully isolate flavanols from other dietary variables. Nonetheless, the practical guidance — swap generic produce for flavanol-dense options — is low-risk and evidence-backed.
Key Findings
- Fewer than 20% of UK and US adults consume the 500mg daily flavanols associated with lower cardiovascular death risk.
- Eating 5 daily fruit and vegetable servings does not guarantee sufficient flavanol intake — specific food choices matter more.
- Plums, cranberries, blackberries, and green tea are among the highest flavanol sources per serving.
- One cup of green tea delivers ~200mg flavanols; one medium apple with skin provides ~110mg per serving.
- Current dietary guidelines may need updating to specify flavanol-rich food choices, not just produce quantity.
Methodology
This is a research summary based on a peer-reviewed study published in Food and Function (June 2026), a credible Royal Society of Chemistry journal. The study used dietary biomarker measurements across 30,000+ participants from UK and US cohorts, providing stronger evidence than self-reported dietary data alone. Notable caveat: Mars, Inc. is listed as a co-institution, introducing potential industry bias.
Study Limitations
Industry involvement from Mars, Inc. introduces potential conflict of interest that should be weighed when interpreting findings. The observational component of the study cannot establish causation between flavanol intake and reduced mortality independent of other dietary factors. Readers should consult the primary Food and Function publication and the original COSMOS trial data for full methodological details.
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