It is a well-known fact that unprotected sex has many risks, but we never talk about all the benefits that sex has.
Let me begin with the most important effect it has on our body: those people who are sexually active have a stronger immune system. It does not mean that they have sex every day, once a couple of times a week, but the more frequently they do it, the stronger their immune system will be.
Having sex – especially in the morning – lowers blood pressure. Since we make our heart work intensely during sex – which also helps lowering the risk of a heart attack – our blood vessels become more flexible, so blood does not need to face so much resistance, thus the pressure in the veins is lower.
If you even have an orgasm during sex, then it is also strengthening your pelvic muscles, with are responsible or bladder control. The more frequently you have an orgasm, the less likely that you will become incontinent later. Or, in case of men, if they have an ejaculation almost every day, or at least twice in three days – including the ones gained via masturbation, too – are a lot less likely to have prostate cancer.
Besides these obviously important effects, we need to know that it also has minor effects. For instance, the more sex you have the more you want, and the change of natural lubrication in a woman's vagina is the proof. Frequent sex leads to quick and intense wetness. You can count it as exercise, as well, if you take three hours of sex for one hour of running. This is also why sleeping is so much easier after a marathon in bed.
So have sex as often as you can to live longer!