articleThe Brief A Penn State study found eating one avocado a day may lower a key heart disease risk factor in adults with obesity. The study suggests adding an avocado to the daily diet may support heart health with one simple dietary change. Eating an avocado a day could decrease the risk of heart disease in adults with obesity, according to a recent study out of Pennsylvania State University. This corresponded to a 4% reduction in heart disease risk. By the numbers:"Four percent is a modest reduction compared with the 14% to 29% lower heart disease risk associated with improving the overall diet," Damani said.