Humor and laughter have many health benefits connected to them. Numerous studies show the impact of laughter on health through measurable improvements in the immune response, blood pressure, blood flow, stress hormones and other health indicators during and following a session of laughter. Some of these effects mimic the body’s physiologic response to exercise leading some to refer to a good laugh as "jogging on the inside."
In his book, Anatomy of an Illness, author Norman Cousins outlines a program of recovery from the debilitating illness known as Ankylosing spondylitis using positive attitude, love, faith, and laughter. Cousins watched Marx Brothers movies to evoke laughter and said, "I made the joyous discovery that ten minutes of genuine belly laughter had an anesthetic effect and would give me at least two hours of pain-free sleep. When the pain-killing effect of the laughter wore off, we would switch on the motion picture projector again and not infrequently, it would lead to another pain-free interval."