timesofsupplements.com/ Students who had sex once or twice a week had the highest levels of immunoglobulin A: 30% higher than those who had no sex, but also those who had sex three or more times a week. In addition, students who were in longer-term, satisfying relationships had the highest levels of the antibody.
That makes sense when you consider research on social support and the immune system. A study of 276 healthy volunteers at the University of Pittsburgh found that those with the most diverse social networks, including not just lovers but family, friends and organizations, were the least likely to catch colds.