"The arrival of a good clown exercises more beneficial influence upon the health of a town than twenty asses laden with drugs."
- Thomas Sydenham, 17th century physician

When was the last time you laughed really hard - a hearty, sidesplitting belly laugh that suddenly grabbed you and sent you reeling out of control? Or you laughed so hard that you forgot what triggered it, leaving you laughing without reason?

Modern science is beginning to confirm that this kind of laughter is not only enjoyable, it's also health-promoting. Laughter is an invigorating tonic that heightens and brightens mood, gently releasing us from tensions and social constraints. Humor offers a valuable perspective on ourselves and our world. What strikes us as funny is usually triggered by a mismatch between what we expect and what we see.

Laughter is an affirmation of our humanness, a face-saving way to express our anxieties, fears, and other hidden emotions to others. It breaks the ice, builds trust, and draws us together into a common state of well-being. Entertainer Victor Borge once quipped, "Humor is the shortest distance between two people."

Humor may be one of our best antidotes to stressful situations. When confronted with a threatening situation, animals have two choices: they can flee, or they can fight. We humans have a third alternative: to laugh. By seeing the humor in a stressful situation, we may be able to change our response to the threat. Humor allows us to distance ourselves and replace paralyzing feelings of anxiety with mirth. When we laugh, we simply cannot be worrying deeply at the same time.

What the Research Shows
Laughter is called "inner jogging." A robust laugh gives the muscles of your face, shoulders, diaphragm, and abdomen a good workout, and sometimes even your arms and legs. Heart rate and blood pressure temporarily rise, breathing becomes faster and deeper, and oxygen surges throughout your bloodstream.

Your muscles go limp and your blood pressure may fall, leaving you in a mellow euphoria. A good laugh can burn up as many calories per hour as brisk walking. During a good hearty laugh your brain orchestrates hormonal rushes that rouse you to a high-level alertness and numb pain. Researchers speculate that laughter triggers the release of endorphins, the brain's opiates. This may account for the pain relief that accompanies laughter.

Norman Cousins claimed to nurse himself back to health from a crippling arthritic condition, in part with old tapes of "Candid Camera" television program and Marx Brothers movies. He claimed that ten minutes of belly laughter had an anesthetic effect and would give him at least two hours of pain-free sleep.

In controlled studies, humor has been shown to lower pain thresholds, reduce stress and even boost immune system function.

In one study, people listening to twenty minutes of Lily Tomlin joking about the telephone company were far less sensitive to pain than those who listened to an academic lecture. The Tomlin tape also blocked pain as effectively as a standard relaxation tape-and you know which one was more fun.

People who use humor a lot are less likely to get upset when faced with negative events. In another study, students had to solve increasingly tricky math problems, becoming highly stressed in the process. Afterwards, they could listen to relaxation tapes, watch an exploration film on the Icelandic River, or see a funny "Candid Camera" scene. The relaxation and funny tapes both reduced stress. But humor only worked for people used to laughing a lot. Laughter needs to be a regular part of your life to get its full benefit.