Are You A Positive Person?

Some studies have shown that an upbeat attitude about aging adds years. But long-term studies conducted at the Stanford Longevity Center show that emotions, more than attitudes, may be the biologic mechanism at work, says Laura Carstensen, the center's director.

"What's the mechanism at work here? Feeling upbeat about your life means you experience less stress, which in turn affects cortisol levels, which can affect health," she says. Stanford researchers periodically assess 19 different emotions in subjects randomly polled over 1 week at 5-year intervals. Having more positive emotions than negative ones is associated with living longer.

Carstensen is a firm believer that while "slow agers" clearly exist, there's more to their stories than lucky genes. "There's mounting evidence that genes play a role in longevity, but genes play a role in almost everything," she says. "They don't express themselves in vacuums -- there are very complex interactions between genes and lifestyle." So all that advice on how to live to 100? Can't hurt to heed it.