Why is smiling good for you?

"You are great ... you are awesome."

So says Hugh Newman, the fictional parking attendant in "Validation," a 16-minute film that has had 1.8 million hits on YouTube.com and is being adopted by everyone from spiritual leaders to corporate executives as a motivational video.

The movie follows Newman (played by actor T.J. Thyne) as he doles out positive affirmations while providing parking validation at a shopping center. He is a master at making people smile.

It is not surprising that feeling good about oneself can lead to feeling good period. Numerous studies have shown associations between positive self-image, self-esteem, optimism and better health. Conversely, people who have low self-esteem, poor self-image, or are pessimistic tend to have more depression and anxiety, weaker immune systems, and poorer recovery from illness.

One study of 999 men showed that those who tended to look on the bright side had a decreased risk of death from heart disease. In recent press for actor and Parkinson's disease spokesperson Michael J. Fox's book "Always Looking Up: The Adventures of an Incurable Optimist" (Hyperion, $25.99), Dr. Holly Andersen stresses the importance of the mind-body connection. "People who have realistic optimism take better care of themselves, live longer and live better. Every study that looks at this reveals the same - people who focus on the part of the glass that is half full, do better," she says.

It isn't just positive thinking that is important, however. The act of smiling itself has been shown to be good for one's health. Simply changing your expression to a smile or mimicking another's smile can cause involuntary biological changes just like those induced by emotions. Research has also revealed that smiling can lower blood pressure, release natural painkillers called endorphins, increase serotonin (a target of antidepressant drugs) and reduce stress. Looking at others' smiles, especially those of babies and children, causes positive chemical changes in the brain. Research on laughter has shown that it relaxes arteries and improves blood flow.

Additionally, doing good deeds and making others feel good about themselves can have health benefits for the giver. One group of researchers at the National Institutes of Health looked at brain activity scans of people as they donated to charity, and found that giving activates the same parts of the brain that respond to more "selfish" rewards like money and sex. Others have shown that altruists and volunteers generally are happier, healthier and live longer.

Mother Teresa, the great humanitarian who lived to age 87, obviously understood the many positive benefits of helping others. She also knew the power of a smile, once stating, "Every time you smile at someone, it is an action of love, a gift to that person, a beautiful thing." In "Validation," Newman's relentless good cheer is a contagious gift that keeps on giving.

The film, written and directed by Kurt Kuenne, can be seen at www.youtube.com (you'll find a link at the top right of this article). But even if you don't watch it, be sure to turn your frown upside down!