In recent years, laughter has become more and more popular as a cure-all. In fact, it may be the next big thing. Laughter yoga clubs have been popping up everywhere. There is some bite behind the bark. Laughter has been scientifically proven to reduce levels of the stress hormone cortisol. Laughing also is a relatively intense cardio workout. It works the core quite thoroughly. Furthermore, melancholy is less common among laughers than non-laughers.