Most people know that eating fruits and vegetables is good for their health. Doctors and nutrition experts have encouraged people for years to eat at least five servings a day. Many people believe that as long as they reach that goal, they are getting all the nutrients they need.
However, a new international study suggests that the story may be more complicated. The researchers found that the types of fruits and vegetables people choose may be just as important as the amount they eat.
The study was led by scientists from the University of Reading, Harvard Medical School, the University of California Davis, and Mars, Inc. The findings were published in the journal Food and Function.
The researchers analyzed dietary information from more than 30,000 people in the United Kingdom and the United States. They also used biological measurements from blood and urine samples to estimate how many flavanols people were consuming.
Flavanols are natural compounds found in certain plant foods. They belong to a large family of substances called polyphenols, which are known for their health-promoting properties.
Scientists have been studying flavanols for many years because they appear to help blood vessels work better and may lower the risk of heart disease. Heart disease remains one of the leading causes of death worldwide, so researchers are eager to find simple dietary changes that may improve heart health.
The study showed that most people are not getting enough flavanols. Fewer than one in five participants reached the amount that has been linked to heart benefits. Even people who regularly ate the recommended amount of fruits and vegetables often failed to consume enough flavanols.
This finding surprised researchers because it showed that healthy eating advice may not always guarantee adequate intake of these important compounds.
Certain foods were found to be especially rich in flavanols. These included plums, blackberries, blueberries, cherries, broad beans, apples with their skins, cranberries, strawberries, and green tea.
Just adding some of these foods to daily meals could greatly increase flavanol intake. A handful of blackberries, a medium apple, or a cup of green tea may make a meaningful difference.
Earlier research, including the large COSMOS clinical trial, found that consuming around 500 milligrams of flavanols each day was linked to a lower risk of dying from heart disease. The new study suggests that many people remain far below this level even when they believe they are eating well.
The findings also raise questions about whether nutrition advice should become more specific in the future. Instead of simply telling people to eat more fruits and vegetables, it may be helpful to encourage certain foods that contain larger amounts of beneficial compounds.
This does not mean other fruits and vegetables are unimportant. Different foods provide different vitamins, minerals, fiber, and other helpful substances. However, the research suggests that food choices within a healthy diet may have a significant effect on heart health.
The study has several strengths, including its very large sample size and the use of biological measurements rather than relying only on people’s memories of what they ate. However, the research cannot prove that flavanols alone prevent heart disease. People’s diets and lifestyles are complex, and many factors influence health.
Even so, the results add to growing evidence that naturally occurring compounds in foods may play an important role in protecting the heart. Choosing a variety of flavanol-rich foods each day may be a simple and practical way to support long-term cardiovascular health.
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Source: University of Reading.
