Laughter is more than just a response to humor.
Laughter is a great workout that boosts the immune system, increases circulation, offers benefits to the heart, and more.
Scientific studies show that laughter has positive effects on the heart, blood vessels, stress hormones, mental health and family relationships. These health benefits of laughter all contribute to smoother overall functioning, which in turn speeds injury healing and helps manage chronic pain.
Helpguide.org has produced webpages with all the information about laughter you could ever want.