It stands to reason that a life without any levity would predispose one to unhappiness and stress. Stress can cause almost any condition to worsen, and depression tends to be associated with IBD. But is there any research to back up the assumption the laughter has health benefits?
There has been a significant amount of research over the years about how laughter and humor affect medical conditions. Not all if it is quality research, however; one of the main problems being the ability to quantify the effects of something as intangible as humor. An example of this is the fact that what some people find funny might not do anything for someone else.
Laughter and HealthIn one review study, the authors concluded that laughter, especially spontaneous laughter, has psychological benefits and almost no negative effects. While they acknowledge that there isn't enough evidence to say that laughing can actually heal you, they go on to recommend the use of laughter as complementary and alternative medicine.
Another review study found that humor doesn't have too many quantifiable positive effects on health, except possibly as an analgesic (painkiller). However, "negative" emotions were noted to have the same effect. The authors concluded that it is strong emotion in general, rather than only humor, that has the analgesic effect. There was not a lot of evidence that humor helped people live longer, relieve stress or resist disease. The authors of this study also noted that much of the research they found for their study had methodological problems.
Laughter and the Immune SystemA series of research studies on the effect of laughter on the immune system found that subjects had measurable physiological responses to watching a funny video for one hour. The positive effects that laughing had on the immune system lasted for as long as 12 hours. The researchers concluded that such laughter could be part of a comprehensive "whole-person" treatment plan.
Laughter and StressAnother study reviewed the evidence that laughter can reduce stress. The research looked at such parameters as heart rate, respiratory rate, muscle relaxation, blood pressure and release of stress hormones. While some of the studies (but not all) showed that laughter or viewing comedy programs did have an immediate positive effect, much of the research had such problems as small sample size or lack of a control group.
Given the currently available research, it is hard to draw clear or definitive conclusions on the health benefits of laughter. Still, it probably doesn't hurt to take your laughs were you can get them.
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