Narrator: This is Science Today. A team of international scientists has made a solid connection between faster "biological" aging and the risk of developing age-related diseases. But what is biological aging? Health psychologist Elissa Epel, of the University of California, San Francisco, says it relates to the length of a feature of our chromosomes called telomeres.
Epel: The telomere length is this type of DNA that caps the ends of chromosomes, kind of like the cap on a shoelace that keeps it from unraveling. The telomeres are very sensitive and vulnerable to damage. So, for example, oxidative stress — these free radicals — can shorten telomere.
Narrator: For well over a decade, Epel has studied stress and found that stress perceptions and stress arousal are related to telomere shortness.
Epel: So, stress is certainly now, entering the realm of traditional risk factors of disease. Whereas earlier people may have raised their eyebrows and said, "Stress? That's just in the head, not in the body."
Narrator: For Science Today, I'm Larissa Branin.