Impotence is a common problem among men and is characterized by the consistent inability to sustain an erection sufficient for intercourse or the inability to achieve ejaculation, or both. Erectile dysfunction can vary. It can involve a total inability to achieve an erection or ejaculation, an inconsistent ability to do so, or a tendency to sustain only brief erections.
The risk of impotence increases with age. It is four times higher in men 60 years compared with 40 years, according to a study published in the Journal of Urology (2000; 163: 460-463). Men with less education are also more likely to experience impotence, perhaps because they tend to have a less healthy life, eat a less healthy diet, drink more and exercise less.