Strawberries and blueberries eaten thrice a week are likely to help women lower their heart attack risk by a third, new research says. The berries have rich levels of compounds called dietary flavonoids, found in foods such as dark chocolate, grapes, red wine, blackberries and eggplant. Dietary flavonoids may prevent heart disease by helping to dilate blood vessels and by countering the build-up of plaque which can cause blockages in the coronary arteries and, ultimately, heart attacks, said researchers, the journal Circulation reports. The researchers found that women who ate the most blueberries and strawberries had a 32 percent reduction in their risk of heart attack compared to those whose ate them once a month or less - regardless of whether they had an otherwise nutritious diet, according to the Telegraph. Eric Rimm, professor, who led the study, said: "Blueberries and strawberries can easily be incorporated into what women eat every week. This simple dietary change could have a significant impact on prevention efforts." Since these dietary flavonoids are very common in fruit and vegetables, it is likely that other foods will yield similar health benefits, he said. The study involved 93,600 women aged between 25 and 42 years. "We have shown that even at an early age, eating more of these fruits may reduce risk of a heart attack later in life," said Aedin Cassidy, professor and study co-author. The findings were independent of risk factors such as age, high blood pressure, family history of heart attack, weight, exercise, smoking, caffeine or alcohol intake.