Feb. 14, 2001 -- Can something that tickles your funny bone keep your skin from breaking out in hives? Maybe so, says a Japanese researcher, who found that people who are allergic to house dust mites, cat dander, and tree pollen had significantly less severe allergic reactions for about two hours after watching a Charlie Chaplin movie.
"These results suggest that the induction of laughter may play some role in alleviating allergic diseases," writes Hajime Kimata, MD, PhD, an allergist in Kyoto, Japan, in a letter to the Journal of the American Medical Association this week.
Kimata studied 26 patients with atopic dermatitis, a condition that causes them to break out in an itchy red rash (the hives). People who are said to be "atopic" are particularly sensitive to allergens such as plant pollens, dog and cat dander, dust, perfumes, cigarette smoke, and many other unavoidable aspects of daily life.
When people who are atopic encounter offending allergens -- say by breathing in a speck of dust -- their immune systems go into overdrive, setting off a series of events that marshal the body's disease-fighting resources to attack the invader. The problem is that the immune system overreacts to an essentially harmless challenge, something like sending in ground troops and air support to stop a playground scuffle.
Allergies are typically tested with a scratch or skin-prick test, in which a small bit of the offending allergen is placed in a small scratch in the skin. The allergen is left in place for about 15 minutes, and the scratch site is then examined for inflammatory reactions such as redness or itching.
But as Kimata found when he showed his patients a video of Modern Times, Charlie Chaplin's comic masterpiece about the role of the common man in the age of machines, their hives following a scratch test were only about one-quarter the size after watching the movie than they were before, suggesting that laughter somehow helped to put the immune system in a better humor. In contrast, their hives were about the same both before and after they watched a video about weather.
"In terms of the immune system, certain antibodies appear to be boosted with laughter. ... IgA, which is an antibody that fights upper respiratory disease, and killer T cells, which ... fight infection, appear to be increased with laughter. The other thing that is a major finding is that serum cortisol, which is a hormone secreted when we're under stress, can decrease," Sultanoff tells WebMD.
Another study, also from Japan, showed that patients with rheumatoid arthritis who were exposed to a traditional form of Japanese humor had decreased blood levels of natural chemicals that can increase inflammation, the major cause of arthritis' painful symptoms.
Also, as reported by WebMD last November, researchers from the University of Maryland found that people with serious heart disease were 40% less likely than healthy people to see the humor in a variety of common situations.