Eating plenty of fruits and vegetables is good advice, but new research reveals a critical gap in how most people approach nutrition: they're likely missing out on compounds that could significantly protect their heart.
A large international study found that fewer than one in five people consume enough flavanols, natural compounds found in certain foods that have been linked to lower cardiovascular disease risk. The surprise is that even people following standard dietary guidelines like eating five servings of produce daily often still fall short.
Researchers from the University of Reading, Harvard Medical School, the University of California Davis, and Mars, Inc., analyzed dietary data from over 30,000 people in the UK and United States. They used biomarker measurements to track flavanol intake and discovered that what you eat matters far more than simply eating more.
"Flavanols can significantly reduce the risk of dying from cardiovascular disease, but only if you consume enough of them," said Dr. Javier Ottaviani, the study's lead author. "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 study, found that consuming 500 milligrams of flavanols daily significantly lowered heart disease death risk. The new findings, published in June 2026 in the journal Food and Function, show most people remain well below that threshold.
Which foods pack the most heart-healthy punch
Not all produce is created equal when it comes to flavanols. A single punnet of plums delivers around 450mg, while cranberries offer about 300mg. Blackberries provide 250mg per 200-gram serving, and a cup of green tea contributes 200mg.
Other solid sources include broad beans at 140mg per small handful, cherries at 130mg per punnet, and medium apples with skin at 110mg. Strawberries, blueberries, and pinto beans round out the list with smaller but still meaningful amounts.
The research suggests pairing flavanol-rich foods strategically. A handful of blackberries alongside a meal, or washing down food with green tea, could meaningfully boost intake of these beneficial compounds and their absorption.
Professor Gunter Kuhnle of the University of Reading noted that current dietary guidance might need refinement. "Five-a-day is the right message, but we may need to think more carefully about which five," he said. "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."
The findings don't suggest people should abandon the five-a-day recommendation. Rather, they highlight that selecting produce strategically could unlock greater heart health benefits from the same effort. As understanding of plant compounds deepens, nutrition guidance has a real opportunity to become more targeted and more powerful.
Author Jessica Williams: "If you're already eating five servings of vegetables daily and still thinking you're done with heart health, this study should shake that assumption, especially when plums and green tea are sitting right there in the produce aisle."
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