Joy . . . or Pain?

· The American Diabetes Association risk calculator, http://www.diabetes.org/diabetesphd (click on Personal Health Decisions).

· The Harvard Center for Cancer Prevention risk calculator, http://www.yourdiseaserisk.harvard.edu/ (includes risk calculator for cancer, diabetes, heart disease, osteoporosis and stroke).

De-Stress

There's a widespread notion that stress can age you. But until recently, no one's been able to prove that, or show why.

Then last year, researchers from the University of California, San Francisco, published research in the Proceedings of the National Academy of Sciences showing that chronic stress speeds the collapse of the ends of gene bundles inside cells, hastening the body's physical breakdown. Researchers measured the lengths of telomeres--the caps at the ends of chromosomes, the molecules that hold genes. In 39 women ages 20 to 50 who had been experiencing long-term stress tied to their care of a child with a serious chronic illness, researchers found shorter telomeres than in a control group of women whose children were healthy.

The takeaway? Say experts, try to manage the stress in your environment. And find better ways to manage your response to that stress through exercise, meditation and relaxation. Controlled studies have tied meditation to lower blood pressure. A study this spring in the American Journal of Cardiology that followed 202 people over several years found lower rates of death from cardiovascular disease and cancer in those who practiced meditation. Moderate and high-intensity exercise has also been found helpful in relieving stress.

And get enough sleep. Studies show that averaging less than seven to eight hours of sleep a night increases the level of the stress hormone cortisol and interferes with normal metabolism.

Be Happy

Some research suggests that happy people live longer. That may sound like good news, but if people could simply make themselves happy as easily as they can modify their diets and take 30-minute walks, well, therapists would be out of business, the self-help industry would collapse and Dr. Phil would just be another loud bald guy who should lose some weight.

Still, the data are compelling.

In one study in last year's Archives of General Psychiatry, researchers gauged the level of optimism and pessimism in 999 Dutch men and women aged 65 to 85, then followed them for nine years. The upshot? The optimists had one-quarter the risk of cardiac death compared with their more pessimistic counterparts. The higher their level of optimism, the more robust their protection. The study also showed that optimistic people had lower death from all causes over nine years.

Other research suggests optimism has a protective effect on the immune system and helps ward off depression.

All right, if you're the cheerful and optimistic type, you've once again lowered your risk of early death. But what if you're not naturally sunny? Martin Seligman is the preeminent researcher in this often-ignored niche of psychology, and his book "Authentic Happiness: Using the New Positive Psychology to Realize Your Potential for Lasting Fulfillment" (Free Press, 2002) provides a how-to guide. According to Seligman, you can experience happiness by absorbing yourself in your job or a hobby and spending time serving others.

British economist Richard Layard, author of "Happiness: Lessons from a New Science" (Penguin Press, 2005), agrees: Becoming happy and optimistic, he says, is essentially taking control of your emotions instead of letting them control you.

"It's a matter of how you organize your attention," said Layard. "You focus on the good parts of yourself and you look forward instead of looking back."

And, presumably, have more "forward" to look at than you otherwise might. ·

Suz Redfearn is a frequent contributor to the Health section.