Most people have heard the advice to eat five portions of fruits and vegetables every day. This recommendation has been a cornerstone of healthy eating campaigns for decades.
The idea is simple: eating more plant foods can help reduce the risk of many chronic diseases while providing important nutrients that support overall health.
Yet a new international study suggests that simply reaching the five-a-day target may not be enough to gain all possible heart-health benefits. Researchers say that the kinds of fruits and vegetables people choose may matter far more than many realize.
The study was carried out by scientists from the University of Reading, Harvard Medical School, the University of California Davis, and Mars, Inc. Their findings were published in the journal Food & Function.
Researchers examined dietary information from more than 30,000 participants in the United States and the United Kingdom. They were particularly interested in flavanols, a group of natural plant compounds that have attracted growing scientific attention in recent years.
Flavanols belong to a larger family of compounds called flavonoids. These substances are produced naturally by plants and are found in a wide range of foods.
Scientists believe flavanols may help keep blood vessels flexible, improve circulation, and support cardiovascular health. Because heart disease remains one of the leading causes of death worldwide, researchers are eager to understand how these compounds might contribute to disease prevention.
The study found that most people were not consuming enough flavanols to reach levels linked with heart-health benefits in previous research. This was true even among many people who successfully met standard fruit and vegetable recommendations.
One reason is that flavanol content varies dramatically between foods. Some fruits and vegetables contain relatively small amounts, while others provide much larger quantities. As a result, two people may both eat five servings of fruits and vegetables each day but receive very different amounts of flavanols.
Foods that stood out as especially rich sources included plums, blackberries, cranberries, cherries, apples with their skin, strawberries, blueberries, broad beans, pinto beans, and green tea. Green tea was one of the most concentrated sources identified by the researchers.
The findings are particularly interesting because they build on earlier evidence from the COSMOS study, one of the largest clinical trials examining flavanols. That research suggested that consuming around 500 milligrams of flavanols each day could significantly reduce the risk of death from cardiovascular disease.
Despite these potential benefits, the new study found that fewer than 20 percent of participants reached that intake level. This suggests that current dietary habits may leave many people short of potentially beneficial flavanol consumption.
Dr. Javier Ottaviani, the study’s lead author, said that many people assume eating plenty of fruits and vegetables automatically provides enough flavanols. However, the research indicates that food selection plays a critical role. Small dietary changes, such as adding berries, apples, beans, or green tea, may substantially increase flavanol intake.
Professor Gunter Kuhnle from the University of Reading emphasized that the five-a-day message remains important. However, he suggested that future dietary guidance could become more specific as scientists learn more about the health effects of individual plant compounds.
The study offers several advantages. Its large sample size improves reliability, and the use of biological markers provides a more objective measure of flavanol intake than food surveys alone. These features strengthen the credibility of the findings.
However, there are limitations. The research does not prove that flavanols alone are responsible for better heart health. People who consume more flavanol-rich foods may also have healthier lifestyles overall. In addition, dietary studies cannot fully account for all differences between participants.
Even so, the findings contribute to growing evidence that not all fruits and vegetables are nutritionally identical. While eating more plant foods remains one of the best dietary habits people can adopt, choosing a wider variety of flavanol-rich foods may provide additional benefits.
The study suggests that future nutrition advice may evolve beyond simply counting servings. Scientists are increasingly interested in identifying which foods deliver specific compounds that support long-term health. As research continues, recommendations may become more targeted and personalized.
For now, the message is clear: eating fruits and vegetables remains essential, but choosing foods such as berries, apples, beans, plums, cherries, and green tea may help people get more of the flavanols linked to a healthier heart.
If you care about heart disease, please read studies that herbal supplements could harm your heart rhythm, and how eating eggs can help reduce heart disease risk.
For more health information, please see recent studies that apple juice could benefit your heart health, and results showing yogurt may help lower the death risks in heart disease.
Source: University of Reading.
