How many times have you heard or said: "Don't kiss me. I have a cold." It makes sense. Close contact spreads colds, so avoiding physical intimacy with cold sufferers should be a sensible way to avoid humanity's most common illness. But a study at Wilkes-Barre University in Pennsylvania shows the opposite, that the close contact of lovemaking reduces risk of colds.
Psychologists Carl Charnetski, Ph.D., and Francis Brennan, Jr., Ph.D., asked 111 college students (44 men, 67 women) their frequency of partner sex: none, less than once a week, once or twice a week, or three or more times a week.
Then the students provided saliva samples. Saliva contains immunoglobulin A (IgA), the body's first line of defense against cold viruses. The more IgA in your saliva, the less likely you are to catch colds.
The once-or-twice-a-week group had the highest levels of IgA, and enjoyed the most protection from colds. This group had 30 percent more IgA than the two groups who had less frequent sex and the group that had sex more often (too much of a good thing).
The researchers also surveyed participants about relationship duration and satisfaction. As duration and satisfaction increased, so did IgA level.
Why would frequent sex in a happy, long-term relationship help prevent colds? It's counterintuitive. Close contact should increase the likelihood of cold transmission--unless interpersonal closeness provides benefits that override the risk of physical proximity. Indeed, a happy, sexually active relationship provides two significant immunological benefits--relaxation and social support.
In good relationships, lovemaking is deeply relaxing. Many studies show that deep relaxation, the kind that results from meditation or visualization/guided imagery, stimulates the immune system. Psychologists at Washington State University took blood samples from 65 people and counted their number of infection-fighting white blood cells. Then the group watched a video that described the immune system. One-third of them did nothing else. Another third was taught to meditate, and practiced twice a day. The final third learned to visualize their immune systems growing stronger, and practiced that visualization twice a day. A week later, the researchers obtained new blood samples. The control group experienced no increase in white cells. But both the meditation and visualization groups did.
Lovemaking is also a powerful form of social support. Many studies show that social support revs up the immune system, and helps prevent colds. At the University of Pittsburgh, psychologist Sheldon Cohen, Ph.D., studied 276 healthy volunteers, who completed a survey of their social ties-to lovers, friends, family, and organizations-and then had live cold virus squirted up their noses. Those with the most social support were least likely to catch the cold.
Which brings us back to the Wilkes-Barre study showing a significant cold-preventive effect for sex once or twice a week in a satisfying, long-term relationship. People often say, "Not tonight, dear, I feel a cold coming on." It's time to update that sentiment: "I feel a cold coming on. Let's do it."