Dr. Lee Berk of Lorna Linda University, Lorna Linda, California, has been investigating the therapeutic effects of laughter for some time. In 2006 it was discovered that anticipating the onset of laughter was enough to boost health-protective hormones. Now, further research has determined that the damage caused by the long-term release of stress hormones is reduced just by getting ready for a laugh.
Blood drawn from experimental volunteers just before they watched a favorite funny movie had 27 percent more beta-endorphins and 87 percent more human growth hormone, compared to a control group who were not expecting to see a funny movie. Beta-endorphins belong to a family of chemicals associated with lifting depression. Human growth hormone helps with the immune function.
During a stressful period, the body produces a number of hormones. Key amongst these hormones are adrenaline and cortisol. Adrenaline is available to give the body the immediate boost it may need to swing into action. Cortisol increases the capacity of the body to repair damaged tissue and it increases glucose into the bloodstream. The combination of hormones works well in situations where a quick response is needed to avoid a nasty incident but the same combination can start to work against the body at times when stress is prolonged.
During periods of prolonged stress, exposure to stress hormones has a number of negative effects on the body. These include an increased risk of heart disease, depression, physical illness, weight gain, stomach pains and diarrhea, and many others. Therefore anything that can alleviate the overproduction of stress hormones is a good thing.