Stress Response
Credit: Joseph Giacomin / Getty Images

Not only has partnered sex been shown to reduce people's reactivity to stress but sex may actually change our brain so that we can better cope with future stress. Scientists in a 2010 study found that rats that had daily sex for two weeks stopped producing extra corticosterone (the rat-equivalent of cortisol). This led them to act less anxious in stressful situations and promoted neural growth that would have otherwise been suppressed by their cortisol-like hormones.