Overall, a third of the men reported erectile dysfunction in the past 3 months. The youngest men reported the highest rates of good sexual function: Seventy-four percent of men younger than age 59 years compared with 10% of men older than age 80 years rated sexual function as good or very good. Many aspects of sexual function, including desire, orgasm, and overall ability, decreased more each decade after age 50 years. Many factors, including increasing age, inactive lifestyle, smoking, obesity, diabetes, stroke, cancer, antidepressant medications, and β-blocker drugs, were associated with increased risk for erectile dysfunction.