Is laughter the new exercise?
Quite possibly. While toning thighs and building muscle mass still require a trip to the gym, other benefits associated with exercise — improved cholesterol and blood pressure, decreased stress hormones, a strengthened immune system and a healthy appetite — can be attained with regular guffaws, studies now suggest.
The latest mirth study, which focuses on the appetite effects of a good laugh, is being presented this week at the 2010 Experimental Biology conference in Anaheim, Calif.
Researchers measured the hormone levels of 14 volunteers before and after they watched a distressing or hilarious video clip. The researchers were particularly interested in two hormones known to regulate appetite: ghrelin, which spurs hunger, and leptin, which cues satiety.
The appetite hormones did not change significantly as people watched the upsetting video (the first 20 minutes of "Saving Private Ryan.")
But after the amusing video clip — either of stand-up comedians or a funny film — hormone levels changed as if the participant had engaged in moderate physical exercise. Specifically, ghrelin levels rose and leptin levels fell, indicating a possible increase in appetite. The lower leptin levels would mean the body isn't getting the "I'm full" message.
Overall, the finding adds to the understanding "that the body's response to repetitive laughter is similar to the effect of repetitive exercise," said study researcher Lee Berk of Loma Linda University in California in a press statement.
Although changes in appetite were not directly assessed, by, say, recording what people ate, the finding could help doctors treat patients who are suffering from loss of appetite but are too ill to exercise, explained Berk.
"It may indeed be true that laughter is good medicine," he said.