n apple a day may actually keep the doctor away – or even better, keep you from getting a life-threatening blood clot. So might an orange or onion, it turns out. All of these fruits and veggies are high in a flavanoid known as rutin, a natural anti-clotting agent, according to a study published Tuesday.
Each year, approximately one third of all deaths in the United States are caused by a heart attack or stroke.
“It’s not always fully appreciated that the majority of Americans will die as the result of a blood clot in either their heart or their brain,” said the study’s senior author Dr. Robert Flaumenhaft, associate professor at Harvard Medical School and a researcher at Beth Israel Deaconess Medical Center in Boston.
Even with the use of existing anti-clotting therapies, such as aspirin, Plavix and warfarin (Coumadin), an estimated 1,255,000 heart attacks and 795,000 strokes occur each year.
Flaumenhaft and his research team at Beth Israel were looking for a compound that could block the action of a clotting agent, a protein called disulfide isomerase (PDI), which they found is rapidly secreted during thrombosis—when a clot forms in a blood vessel.
But because PDI is necessary for the production of certain proteins, they had to hunt for a compound that could block only certain PDI proteins. When the researchers tested more than 5,000 compounds, rutin emerged as the most potent.
Rutin is found in many fruits and vegetables, including apples (especially the peels), berries, citrus fruits and onions, as well as teas and buckwheat. It is also sold as an herbal supplement. Fortunately, studies have shown that flavanoids are well tolerated and safe.
The researchers then tested rutin to see if it would prevent blood clots in a mouse model.
“Rutin proved to be the most potently anti-thrombotic compound that we ever tested in this model,” said Flaumenhaft. In addition, epidemiologic studies have found that a diet high in flavonoids is associated with a lower risk of heart attack and stroke.
Though clinical trials in people still need to be done, the research is promising and clearly demonstrated that targeting PDI is an effective anti-clotting therapy. Because the Food and Drug Administration has already established that rutin is safe, the flavanoid can be tested in a clinical trial relatively quickly.
Laurie Tarkan is an award-winning health journalist whose work appears in the New York Times, among other national magazines and websites. She has authored several health books, including "Perfect Hormone Balance for Fertility." Follow her on Twitter and Facebook.