Suddenly, this can no longer be a family blog.

Parents, if your children are reading this along side you, cover their eyes.

Alright. Is it secret? Is it safe?

Here we go. Thanks to New Scientist:

Stuart Brody, a psychologist at the University of Paisley, UK, compared the impact of different sexual activities on blood pressure when a person later experiences acute stress. For a fortnight, 24 women and 22 men kept diaries of how often they engaged in penile-vaginal intercourse (PVI), masturbation or partnered sexual activity excluding intercourse. After, the volunteers underwent a stress test involving public speaking and mental arithmetic out loud.

Volunteers who'd had PVI but none of the other kinds of sex were least stressed, and their blood pressure returned to normal faster than those who'd only masturbated or had non-coital sex. Those who abstained had the highest blood-pressure response to stress (Biological Psychology, vol 71, p 214).

I really really really wish I had something to add to this. But you know? I think it really speaks for itself. Now go act on your knowledge.