As reported in the journal Heart, researchers at the University of Maryland Medical Center in Baltimore collected a total of 160 measurements of brachial artery flow from the participants a minute before and after phases of laughter or sadness. The brachial artery, which runs from the shoulder to the elbow, is a good indicator of blood flow throughout the body.
According to the researchers, brachial blood flow was reduced in 14 of the 20 participants after they watched segments from the sad movies. Blood flow was increased in 19 of the 20 participants after they watched clips from comedy movies.
The difference in blood flow response while watching sad or happy movies was more than 50 percent. The effect of watching a sad movie caused the same kind of reduced blood flow as remembering episodes of anger and doing mental arithmetic, the study authors said. In contrast, watching a comedy boosted blood flow to a level equal to that of doing aerobic exercise or getting started on a cholesterol-lowering statin treatment.
The findings were first presented last year at the American College of Cardiology scientific sessions meeting in Orlando, Fla.