Yes, it's true. Laughing does help you live longer.

That shouldn't come as a surprise, actually. Think about it; how do you feel when you laugh? You feel good. Don't you? I mean, show me the guy who, while he's laughing, tenses up because he's thinking about punching his neighbor in the nose over a property-line dispute, or the wife, while her head is tilted back in a fit of high-pitched laughter, is simultaneously clenching her fists because she is enraged at her husband, and I'll show you a couple of freaks of Nature.

No, laughing relaxes you. Completely. Laughing (I'm talking about honest-to-goodness laughter, not the phony kind) banishes all stress, all negative thoughts, all your cares and woes, at least temporarily. That has to be a good thing. And it is.

In fact, did you know that world-renowned medical centers teach that laughing makes you live longer? When it comes to your health and longevity, laughing, it turns out, is no laughing matter. It plays a serious role in your overall well-being.

In fact again, even if you're a pessimistic sourpuss, you can still benefit from humor. Whether that humor is found in sick jokes, or you laugh at the misfortunes of others, or you cackle when you pull one wing off a fly and watch it spin helplessly, your chortles can help your body fight the aging process. And you'll probably live longer than you should be allowed to. (Just kidding, just kidding!)

If you want a quasi-scientific explanation for how laughter works its wonders, here it is:

Laughter releases endorphins in your body. Endorphins are one of your body's defensive weapons against disease. By relieving stress, this chemical strives to keep your blood pressure at its heart-healthy best and also fights a battle against physical problems that can lead to heart attacks. It has been clinically proven that people who do not have heart attacks tend to live longer. Seriously.

Laughter also strengthens your immune system. It also gives you more energy. And regular bouts of merriment can help lessen your pain, whether physical or emotional.

And not only does laughing help you live longer, it lets you look good while you're doing it. How so? Well, laughter causes feeling of happiness (duh!) and gives you a sense of well-being. And when you're happy, it shows up on your skin. And who doesn't want happy-looking skin?

Furthermore, because you're more relaxed, you'll look and feel 10 times younger. (To quote a certain U.S. senator, that "10 times" phrase was "not intended to be a factual statement." You could leave it out entirely and I would still make my point.)

Speaking of politicians, here is a stress test you can try at home:

I think anyone would concede that being president of the United States is a stressful job. Compare a photo of George W. Bush in 2001, when he first took office, to a photo of him in 2009, when he left office. Whoa! Then compare a photo of Barack Obama in 2009 to a photo of him now, little more than two years into the job. Where did all that grey hair come from?

The inescapable conclusions are that 1) Bush and Obama should laugh more, and that 2) stress has achieved a level of bipartisanship that today's crop of politicians seems utterly incapable of.

But even if you're not in a particularly high-stress job or you don't have a high-stress life, you can still get the rewards that laughing can give you. Laughter can give you the mental fortitude, for example, to handle people who aren't easy to be around.

It can also help you be better prepared to roll with life's punches. If you can't find humor in almost every stressful situation you encounter, you aren't looking very hard. If you can find it, you'll be adding years to your life.

And here is an indirect, but extremely important, benefit of laughter: Ask yourself, who are your best friends, your closest, very, very best friends in the world? People you would trust with your life. I can't answer for you, of course, but in my case in every single instance it is the friends who make me laugh. And let me tell you, having even three or four friends like that can absolutely lengthen your life.

Of course, laughter isn't the only weapon you should have in your anti-aging arsenal. Yes, it will help you live longer, but that doesn't mean that you can ignore all the other rules of good health.

Rules such as eating the right foods, getting plenty of rest, exercising regularly, not ever, ever smoking, and drinking only in moderation are rules you shouldn't ignore. Just as important is making sure you take vitamins and health supplements and keep your skin looking good by investing in high-quality skin-care products.

Do all that, and you will not only live longer, you'll get the last laugh in life.