Growing evidence confirms suspicions that laughter is not only fun, but good for us! WebMD reports that laughter and moderate exercise share a host of healthful effects. According to Dr. Lee Berk's research, appetite hormones behave the same way after a good giggle as they do after a few workout reps. In science-speak: leptin goes down and grehlin goes up. Berk's volunteers watched stressful videos and hilarious videos (in no particular order) while their hormones were monitored. The results show comedy may be good for more than a chuckle.