How can the worlds oldest people also lead unhealthy lives

Wanna live a long and healthy life? You might as well knock back the booze and smoke 'em if you got 'em -- it turns out the key to longevity lies in the genes.

The race toward discovering the key to this type of longevity still continues. However, scientists have figured out that somewhere within our genetic makeup, some of us appear to have a mutation -- a leg up, really -- that staves off cellular death. It's also possible that if researchers can identify the gene or genes responsible for long life, the rest of us can benefit through gene therapy.

HowStuffWorks "How can the world's oldest people also lead unhealthy lives?"