You know kissing makes you feel good emotionally, but it also has amazing physiological benefits.

Saliva is full of substances that ward off bacteria, viruses, and fungi. These substances are responsible for your immune responses. Exchanging saliva can boost your immunity by exposing you to new germs.

Besides fighting infections, kissing helps control your autoimmune response to common allergies. A Japanese study revealed that people who had allergies to dust mites or pollen showed a significant reduction in allergic response after kissing for 30 minutes freely with their lover or spouse.

Kissing also reduces blood pressure by dilating blood vessels, increasing blood flow throughout the body.

Kissing may also lower total cholesterol. A 2009 study found that couples who increased their incidence of romantic kissing showed improvement in total serum cholesterol. That can lower the risk of heart attack and stroke.