Stress and Telomeres Again
Scientists have been exploring links between the biochemistry of stress and more rapidly shortened telomeres for a couple of years now. Here's more from Forbes: "We examined healthy women and found that psychological stress was related to [shortened telomeres]. As a result, the immune system of the stressed-out women is apparently aging at a faster rate. The treatments for this problem are what you might expect. 'Everything we already know about fighting off chronic disease, like getting sufficient sleep, staying active throughout life, and having a healthy diet' may stave off premature aging of the immune system." Shortened telomeres are linked to a number of age-related conditions. Stress is clearly a system-altering phenomenon for the human body, so the hypothesis here is plausible - but correlation is not causation. From where I stand, more delving into the mechanisms is needed to demonstrate that the stress response is acting as a significant source of life-shortening cellular damage.
Link: http://www.forbes.com/forbeslife/health/feeds/hscout/2006/08/11/hscout534367.html