Reference: More sex is good, Bangkok Post, July 10, 2008

A survey by Finnish scientists showed that older Finnish men who had sex less frequently than one time a week had an erectile dysfunction rate of 7.9% while those who did it more than once a week suffered an erectile dysfunction rate of only 3.2%. They concluded from these data that infrequency of sex causes erectile dysfunction. Kindly note that survey data may contain correlation information but they do not contain causality information. The observed correlation could mean that sex infrequency causes erectile dysfunction as claimed, but it could also mean that erectile dysfunction causes sex infrequency, or that a third unobserved variable causes both sex infrequency and erectile dysfunction. It is not possible to determine which of these causalities is true without a controlled experiment.

Cha-am Jamal
Thailand