Cranberries are not often thought of except on major food-focused holidays like Thanksgiving and Christmas but adding cranberries to your everyday diet could be a good decision. Researchers in London found daily cranberry consumption significantly improves cardiovascular health.
Scientists from King’s College completed a double-blind, placebo-controlled study with 45 men who consumed 9 grams of freeze-dried cranberry powder a day for a month. That’s equivalent to 100 grams (1/2 cup) of fresh fruit. The study participants showed a “significant improvement” compared to the placebo group in flow-mediated dilation (FMD), which signals enhanced heart and blood vessel function.
Researchers use FMD to measure how blood vessels widen when blood flow increases and it is considered a sensitive biomarker of cardiovascular disease risk. The results of the study were published in the journal Food & Function.
"The increases in polyphenols and metabolites in the bloodstream and the related improvements in flow-mediated dilation after cranberry consumption emphasize the important role cranberries may play in cardiovascular disease prevention," said senior study author Dr. Ana Rodriguez-Mateos. "The fact that these improvements in cardiovascular health were seen with an amount of cranberries that can be reasonably consumed daily makes cranberry an important fruit in the prevention of cardiovascular disease for the general public."
Health experts believe insufficient consumption of fruits and vegetables is one of the top modifiable behaviors when it comes to the lowering the risk of cardiovascular disease. There is growing evidence of how polyphenols improve heart health. Cranberries are unique in that they are rich in proanthocyanidins, a type of polyphenol found in greater abundance in that fruit than in other fruits.
The study participants initially showed improvements in FMD two hours after consumption and then it led to longer lasting or chronic improvement as the polyphenol levels grew.
"The findings provide solid evidence that cranberries can significantly affect vascular health even in people with low cardiovascular risk," said study co-author Dr. Christian Heiss. "This study further indicates that specific metabolites present in blood after cranberry consumption are related to the beneficial effects."