We all know that laughter is the best medicine. If not the best, certainly good for you. Scientific studies have shown that mental stress can restrict blood flow to the heart. But now a study has linked laughter to increased blood circulation. Laughter appears to cause the tissue inside blood vessels to expand. Medical science feels that laughter may be important to increase cardiovascular health.

A recent study was conducted at the University of Md. of twenty men and women, all healthy. To make them laugh, they watched part of the movie "Kingpin," a 1 hour comedy. To create the opposite emotions, they also watched the brutal beginning of "Saving Private Ryan."

The clinicians used ultrasound to measure changes in blood flow through an artery in the arms of participants. Blood flow increased in 19 of the 20 participants after watching "Kingpin.". That is a 22% increase. The study leader, a Dr. Miller feels that is similar to the effects of aerobics. Blood flow decreased in 14 of the twenty people after they watched "Saving Private Ryan," an decreased average of thirty five percent.

Studies have shown that reducing stress can reduce disease in the body. When the body is under stress, it produces hormones such as adrenalin and cortisol. Cortisol is related to anxiety and fearfulness and adrenalin gives us us the "fight or flight element". Too much of these hormones can be bad for the immune system. Dr Miller observed that the study could not explain how laughter is responsible for the effects observed but he assumes it is either from a release of chemicals or muscle movement.

Clinical studies have shown laughter may cause the body to release endorphins, like when exercise takes place. Miller states that these endorphins may block the effect of stress hormones and cause the blood vessels to expand. Laughing may also influence the release of nitric oxide, which too expands blood passages. The results were presented at a meeting of the American College of Cardiology. Dr. Miller does not suggest to replace exercise with laughter, but he says just a quarter hour of laughter could absolutely make one healthier, not to mention happier.