Eating avocados might lower your risk of cardiovascular disease and heart attacks. In a new study published in the Journal of the American Heart Association, Harvard researchers followed over 100,000 men and women who completed dietary questionnaires every four years for three decades. None had a history of heart disease or stroke at the beginning of the study, but 11 percent of the women and 16 percent of the men experienced or died from a heart attack or stroke during those three decades. The researchers determined that people who ate at least two servings of avocado a week were 21 percent less likely to have a heart attack than people who never or only rarely ate them. They found no link between avocado intake and stroke. The study suggests that occasionally replacing butter and other fatty foods with avocado could lower your risk of cardiovascular and coronary heart disease.