We've all been told that men think about you-know-what far too often — every seven seconds, by some accounts. Most of us have entertained this idea for long enough to be sceptical. However, rather than merely wonder about whether this is true, stop for a moment to consider how you could — or could not — prove it. If we believe the stats, thinking about sex every seven seconds adds up to times an hour. Or approximately 7, times during each waking day. Is that a lot?

Editor's note: Dr. She is founder and director of the Women's Mood and Hormone Clinic. CNN -- Although women the world over have been doing it for centuries, we can't really blame a guy for being a guy.

Sex is so much fun that you just feel like doing it over and over again. The desire to do it again and again is never-ending. But how much sex is good for you?