:] Laughter

It's been said that it's potent enough to lower blood pressure, ward off colds and stifle the flu—and help you to sleep better and even lose weight. What is this miracle tonic and where can it be found? Down deep, in your own belly. No joke. Good old-fashioned laughter is getting a lot of attention for boosting the immune system and improving overall health. How? The answers vary, but the theory goes like this: Just as grief and anger can suppress the immune system, mirth can strengthen it. Laughter creates a unique physiological state, with changes in the immune system opposite to those caused by stress. Regardless of its physical effects, laughter remains good for the soul—so boost your daily dose with these:

Socialize. People laugh nearly 30 times more often in social settings than they do when alone. So get together with friends, family and coworkers for a chuckle.

Look for a shared sense of humor in friends. It can provide the foundation for a life-long bond.

Make an effort. In conversation, be animated, spice it up or exaggerate for humor's sake. It's easier to be dull than to be witty, so don't be lazy.

Laugh early—and laugh long. Send a quick and funny e-mail to a friend before heading to work, or catch a morning cartoon with the kids. Enjoying a few minutes of looniness in the morning can change your mood for the rest of the day.