It started with a sushi lunch, followed by a 40-minute educational lecture. Afterward, Ohta’s blood-sugar level soared to 338 milligrams per deciliter. The next day, Ohta had the same lunch, but this time he attended a comedy show. Laughing apparently helped: Ohta’s blood sugar topped out at 252mg/dl–an improvement of 25 percent. Dr. Koichi Kawai and his team found similar results in the 18 other patients who participated in the study. Expressions of “positive emotions” like laughter may act on the body’s endocrine system to suppress blood-glucose levels, they report. Says Ohta: “I was very surprised by the result.”
The study team is now conducting a more rigorous experiment to see if the effects of laughter are long-lasting. They’ve asked 20 patients to measure their blood-glucose levels before and after watching TV or video comedy shows for six months, and this time they’ll give them DNA tests. “What I really want to know is how the mechanism of laughter works on our genes,” says Kazuo Murakami, a genetic engineer at Tsukuba University who first suggested the experiment. Ohta has volunteered for this experiment, too. “I learned a simple lesson,” he says: “A good laugh does you good.”
