In medical school, we were taught the forty-over-forty rule: 40 percent of men over age forty have erectile dysfunction. Men with erection difficulties in their forties have a fiftyfold increased risk of having a cardiac event (like sudden death).36 We used to think of erectile dysfunction in younger men (those under age forty) as “psychogenic”—meaning it’s all in their heads. But now we’re realizing that ED is more likely an early sign of vascular disease.
