“We’ve long known that the ability to laugh is helpful to those coping with major illness and the stress of life’s problems. But researchers are now saying laughter can do a lot more -- it can basically bring balance to all the components of the immune system, which helps us fight off diseases…Laughter reduces levels of certain stress hormones. In doing this, laughter provides a safety valve that shuts off the flow of stress…These stress hormones suppress the immune system, increase the number of blood platelets (which can cause obstructions in arteries) and raise blood pressure.
When we’re laughing, natural killer cells that destroy tumors and viruses increase, as do Gamma-interferon (a disease-fighting protein), T-cells, which are a major part of the immune response, and B-cells, which make disease-destroying antibodies” (www.howstuffworks.com).
There is actually an organization dedicated to helping inform the medical community about these facts. They also provide DVD players and funny classics to Cancer patients (LaughterHeals.org)