Want to protect your brain, improve your memory, slash your stress levels and boost your quality of life all at the same time?

Then go ahead and laugh.

New research confirms that there is some truth to the saying "laughter is the best medicine" -- and it's especially effective at protecting the brain.

In a series of experiments, seniors who watched funny videos did better on memory tests than seniors who didn't watch the videos. The laughing seniors enjoyed measurable improvements in memory recall, learning ability and sight recognition.

And while even healthy seniors saw improvements after watching the video, the biggest boost of all went to seniors with diabetes.

Laughter is also a great way to blow off steam and ease stress, and the study confirms that, too -- because seniors who laughed had lower levels of cortisol.

That's the so-called "stress hormone," and despite the name, it's not always bad. There are times when we need it.

But too much too often, or chronically high levels, can promote inflammation and lead directly to disease.

Laugh a little more, and your levels of these hormones will fall as your worries fade into the background.

And that's not all laughter can do.

Laughter can also promote relaxation, lower blood pressure and ease pain (both physical and mental). Some hospitals are even turning to laugh therapy to help patients recover.

Plus, laughing just makes you feel good.

So go ahead and watch some comedy or joke around with your friends. It's not just fun.

It's good for you, too.