The risk of cancer or heart disease won't scare a heavy smoker, but this may make him think twice: men who smoke are at a high risk of developing erectile dysfunction (impotence). And the larger the number of daily smoked cigarettes, the higher the risk.

A new research investigated 4 763 Chinese subjects aged 35 to 74, who did not suffer of any blood vessel condition and who stated they had been sexually active six months before the investigation.

"The association between cigarette smoking and erectile dysfunction was found in earlier studies. However, most of those studies were conducted in patients with hypertension (high blood pressure), diabetes and cardiovascular disease. What distinguishes this study is that it is the first to find this association among healthy men.", said first author Dr Jiang He of Tulane University School of Public Health, New Orleans.

Smokers presented, on average, a 41 % higher likelihood of being impotent compared to non-smokers, as the authors mentions in the American Journal of Epidemiology. Those who smoked a maximum of 10 cigarettes daily presented a 27 % higher likelihood of impotence; 11 to 20 cigarettes daily was the equivalent of a 45 % increased risk for erectile dysfunction; and over 20 cigarettes per day boosted the chances for erectile dysfunction by 65 %.

The team forecasted that 22.7 % of all impotence cases among Chinese men without vessel-affecting diseases could be caused by tobacco smoking.

The worrying issue is that even after quitting smoking, the men displayed the same risk for developing erectile dysfunction as if they still smoked. The values remained the same for former smokers as for active smokers. "This study really has a strong message for young men. It may get their attention if they know that smoking is associated with erectile dysfunction - even in the healthy population. So the message is: Don't start.", he said.

Other studies showed that smokers had weaker sleep non-erotic erections, when the penis tissues are blood flooded and fed. Impairment in these erections induced poor condition of the penile tissue and vessels (involved in producing the erection) in smokers.