A laugh a day keeps the doctor away

A hearty laugh a day may keep the doctor away, say the findings of a unique study. Whereas previous studies have examined how negative emotions can adversely affect our health, this study took a new spin--they measured the affect of watching a funny movie on the ability of heart blood vessels to expand. And they found some surprising results--laughing increased blood flow as much as a 15- to 30-minute workout.

The ability of blood vessels to expand is known as vasodilatation. Poor vasodilatation means that passageways may be blocked and blood flow may be cut off. The result is an increased risk of heart attacks and strokes.
Blood flow decreased by about 35 percent after experiencing stress
Blood flow increased by 22 percent after laughing, which is equivalent to what happens after a 15- to 30-minute workout

Past studies have found that stress hormones like adrenalin and cortisol, which is released when a person is stressed, may harm the body by suppressing the immune system and constricting blood vessels. On the other hand, the researchers believe laughing causes the body to release beneficial chemicals called endorphins, which may counteract the effects of stress hormones and cause blood vessels to dilate.

In a similar manner, laughing may also boost the immune system and reduce inflammation, which is thought to increase the risk of various health problems. The researchers say they have a long way to go before their hypothesis will be proven, but they point out that there's no downside to laughing and they have no problem recommending it to their patients.