Sci is at SciAm blogs today, looking at a recent study which examines the effects of stress on telomerase. Telomerase lengthens your telomeres, and telomeres help keep your cells from aging. In times of stress, you might want to keep your telomeres long. Head over and check it out.
EDIT (3/26/13): Based on reader comments, I think this post was too credulous. I have made corrections in the original post in italics.