Excerpted from THE ECONOMIST April 7, 2011:
Telomeres are to chromosomes what plastic caps are to shoelaces—they stop them fraying at the ends. Unlike shoelaces, though, chromosomes replicate themselves from time to time as the cells they are in divide. This shortens the telomere and, after 50-70 such divisions, a chromosome can grow no shorter and the cell it is in can divide no more.
It has been known for some time that chronic stress causes premature shortening of the telomeres. What has not been clear is whether this is a one-way trip, with each stressful period turning the telomeric ratchet irreversibly. This week, though, at a meeting of the American Association for Cancer Research, a group of researchers led by Dr Edward Nelson showed that it isn’t. Their research suggests that stress management not only stops telomeres from shortening, it actually promotes their repair.