Study: Even 'Healthy' Eaters May Miss Heart-Protecting Flavanols

According to new research led by scientists from the University of Reading, Harvard Medical School, the University of California Davis, and Mars, Inc., most people are not getting enough flavanols, natural compounds that support heart health. The study, published June 8, 2026, in the journal Food and Function, analyzed dietary data from more than 30,000 people in the United Kingdom and the United States using biomarker measurements to assess flavanol intake.

The findings show that fewer than 20% of individuals reached the flavanol intake level associated with heart health benefits. Even many who regularly consumed the recommended five servings of fruits and vegetables per day fell short. Dr. Javier Ottaviani, lead author, said: “Flavanols can significantly reduce the risk of dying from cardiovascular disease, but only if you consume enough of them. Most people assume that eating plenty of fruit and vegetables covers this, but what this research shows is that the specific choices you make matter far more than the total amount.”

Previous research, including the COSMOS trial—the largest clinical study on flavanols—found that consuming 500 milligrams of flavanols daily significantly reduced the risk of death from heart disease. The new study indicates most people remain well below that level, even when following standard dietary guidelines like the NHS Eatwell Guide.

Researchers identified the richest dietary sources of flavanols per serving: Plums (500g) – about 450mg; Cranberries (250g) – ~300mg; Blackberries (200g) – ~250mg; Green tea (250ml) – ~200mg; Broad beans (80g) – ~140mg; Cherries (400g) – ~130mg; Apples with skin (200g) – ~110mg; Strawberries (200g) – ~90mg; Blueberries (150g) – ~80mg; Pinto beans (40g dry) – ~70mg.

The results raise questions about whether current nutrition recommendations could be improved. Professor Gunter Kuhnle of the University of Reading noted: “Five-a-day is the right message, but we may need to think more carefully about which five. Different fruits and vegetables offer very different nutritional benefits beyond vitamins and minerals, and as our understanding of these compounds grows, there is a real opportunity to make dietary guidance more specific and more effective. This research is a step towards understanding what that might look like in practice.”