A lot of the lauded health benefits of sexual activity may actually stem from the fact that healthy people generally do it more. Still, the value of maintaining a good sex life when you're in an intimate relationship is undeniable. "Clearly, the best, most beneficial effect [from sex] is the enhancement of the quality of the relationship. That is truly a huge impact that it can have," says Khera. A healthy sex life can provide both partners with enhanced relaxation, a self-esteem boost, and more intimate feelings toward each other. All of those can add up to a stronger and more supportive relationship, which confers significant health benefits all its own.