4. Protects his prostate
Catholic priests have an elevated chance of dying of prostate cancer, and studies point to celibacy as a factor.
In 2003, research on middle-aged Australian men found that those who averaged at least four ejaculations a week had a one-third lower chance of developing prostate cancer than those who had fewer. "When you drain the pipes, as it were, you have less clogging," says Irwin Goldstein, MD, head of sexual medicine at Alvarado Hospital. Though the results of the study were clear, the reasons they occurred were not, says Goldstein, who calls for more research.
5. Lowers stress
Got a big presentation coming up at work? Spend some time in bed beforehand.
A 2005 study found that men and women who had engaged in intercourse in the 2 weeks before a stressful day had an easier time while doing public speaking and some verbal arithmetic. During their presentations, their systolic blood pressure (the first number in a blood-pressure reading) increased less and then dropped back to its normal level at a faster rate than that of people who had no sexual relations or had other forms of sex, including noncoital interactions or masturbation. One theory about why this occurs is that intercourse requires more complex brain activity; another idea is that it stimulates a number of important nerves not triggered during other sexual activity.
6. Revs your immune system
It's not just apples — sex helps keep the doctor away too.
Research from Wilkes University showed that college students who engaged in sex once or twice a week had 30% higher levels of infection-fighting antibodies than did their abstinent classmates. In 2004, German scientists produced similar results: Blood tests showed that arousal and orgasm in men increased levels of certain pathogen-fighting white blood cells. The effect is comparable to that of other stress-busting activities, such as exercise and listening to music, which also boost secretion of certain proteins that defend the body against infection.
7. Keeps down below healthy
A healthy sex life can prevent dryness — and the pain that comes with it.
Scientists in New Jersey found that postmenopausal women who had sexual relations more than 10 times a year had less evidence of vaginal atrophy than those who reported less frequent sex. That's a sign of healthy tissues, says Sandra Leiblum, PhD, a New Jersey sex therapist who helped conduct the study. Arousal brings blood to the vagina, which delivers nutrients and oxygen. Keep using this part of your body, and you'll help prevent the tissue from becoming thinner and less elastic as you age, so intercourse can remain comfortable and pleasurable.