Among 439 consecutive erectile dysfunction patients, 26%—or 114 of the men—were under age 40, the study shows. The researchers assessed those patients based on dozens of lifestyle and health factors like testosterone levels, smoking history, body mass index, length of relationship with sexual partner, and drug use. The results indicate younger men aren’t suffering from ED for the same reasons as their fathers (and grandfathers).      While the sub-40 ED sufferers had normal testosterone, BMI, and hypertension levels—all of which tend to cause dysfunction in older men—they were more likely than older ED patients to be addicted to cigarettes and illicit drugs like cocaine and marijuana. Psychological factors like anxiety or depression may also play a role in younger men’s sexual problems, the researchers hypothesize.  Heightened pornography exposure could additionally contribute to the new ED trend, according to findings published in the Journal of Sexual Medicine. Men who start watching porn regularly in their teens or who currently view porn every day are significantly more likely to experience low libido or a weak erection, the research shows.  So if you’re under 40 and having problems in the bedroom, quitting smoking, ditching drugs, and limiting your porn-watching habit will likely improve your performance, the research indicates. If all else fails, prescription drugs may also prove effective—though the long-term health and sexual-function ramifications of taking ED drugs at a young age still aren’t well-understood.  More from Prevention: The Sex Issue 75% of Men Aren’t Dealing With