Seems sex reduces depression, reduces stress, and brings on sleep. All of which contribute to a longer life.
Given that long-term stress seems to cause all manner of diseases including type 2 diabetes, some cancers including liver and stomach cancer, and heart disease leading to heart attacks, then anything you can do to relieve stress has to be a good idea.
Sex daily seems to be about the right amount from the studies conducted, but certainly at least three times a week is recommended.
Have I mentioned before that I have type 2 diabetes?