Study Highlights Heart Benefits of Flavanol-Rich Fruits in Daily Diet

Your heart may benefit more from which fruits and vegetables you eat than simply how many servings you consume, according to a major new international study.

Researchers from the University of Reading, Harvard Medical School, the University of California Davis, and Mars, Inc. analyzed dietary data and biomarker measurements from more than 30,000 people in the United Kingdom and the United States.

Their findings, published in Food and Function, revealed that fewer than 20% of participants consumed enough flavanols—natural plant compounds linked to cardiovascular protection—to reach levels previously associated with a lower risk of heart disease.

Earlier research, including the large COSMOS clinical trial, found that consuming around 500 milligrams of flavanols daily can significantly reduce the risk of dying from cardiovascular disease. However, the new study showed that many people fall far short of this target, even if they follow standard healthy eating advice such as consuming five portions of fruits and vegetables a day.

Researchers say the specific foods chosen make a substantial difference. Among the richest dietary sources of flavanols were plums, cranberries, blackberries, green tea, broad beans, cherries, apples with skin, strawberries, blueberries, and pinto beans. For example, a single cup of green tea can provide about 200 milligrams of flavanols, while a serving of blackberries contains approximately 250 milligrams.

According to the researchers, adding flavanol-rich foods to daily meals could be a simple way to improve heart health. A handful of berries, an apple with its skin, or a cup of green tea may help increase intake of these beneficial compounds.

The findings also raise questions about whether public health recommendations should move beyond general advice such as “five-a-day” and provide more guidance on the types of fruits and vegetables people choose. Scientists believe that as understanding of plant compounds grows, future dietary guidelines may become more specific, helping people make choices that offer greater protection against cardiovascular disease.

REFERENCE: Ottaviani, J. I., et al. (2026). Adhering to dietary guidelines does not yield flavanol intake levels associated with beneficial cardiovascular effects. Food & Function. DOI: 10.1039/D6FO00867D. https://pubs.rsc.org/en/content/articlelanding/2026/fo/d6fo00867d