How Exactly Do We Age?

Scientists have spent years researching this question, and in recent years have narrowed it down from over 300 theories to just a handful.

They've loosely divided these remaining theories into two categories: biological processes, and wear and tear. So far, we don't have a lot of control over the first category, which deals with how our genes and cells act (but that could change, fast).

But the second category deals with damage from food, drink, smoking, stressm and the environment. Read the rest of the story here:

http://www.aarpmagazine.org/health/living_longer_science.html