The Boston University School of Medicine had a study which involved 600 men between the ages of 40 and 70 who at first had zero indications of impotence problems.

After eight years, 17% of the participants developed impotence.

The participants who were involved in activities such as smoking, heavy drinking or were obese in the beginning of the study were the most likely to report erection problems in the end.
On the other hand, the men who have quit smoking, stopped drinking and lost weight along the way did not seem to improve their erections either.

But the men who took positive action, such as regular exercise reduced their chances of being impotent.

To be continued…