InflammationStudies by Lee S. Berk, PhD, Loma Linda University in California: laughter can reduce the sedimentation rate (a measure of inflammation), increase number of immune cells, increase endorphins, increase IgA salivary concentrations, enhance respiration, and decrease cortisol. (Howard, Pierce, J., PhD. The Owner’s Manual for the Brain. p 170-172. NY: Bard Press, 2000.)