Illustration: Mark Matcho

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Catch Fewer Colds
A study from Wilkes University in Pennsylvania found that people who had sex once or twice a week enjoyed a boost in their immune system, thanks to a 30 percent increase in immunoglobulin A, the infection-fighting antibody found in the respiratory and gastrointestinal tracts. One caveat: Subjects who had sex more than three times a week actually had lower levels of the antibody than those who had less sex. Researchers believe that in moderation, the release of chemicals during orgasm may enhance your immune function, while too much of these chemicals may suppress it.