Since attraction is often the precursor to sex, it makes sense that sex can also make you more attractive. Post-coitus, your skin may glow from the increased circulation of oxygen and the stress reduction can help reduce acne. One commonly cited study from 2004 also found that people who have sex a couple times a week have 30 percent higher levels of immunoglobulin A – an antigen that can help your body ward off illness – than abstainers. However, people having sex three or more times a week had lower levels than everyone else. According to the BBC, the researchers said this may be because these people are more likely to be in stressful relationships.