It is not only our spirits that are eroded by constant anxiety and worry; it seems that our chromosomes are also, literally, worn down by stress. This is the conclusion of a study published in the Proceedings of the National Academy of Sciences that asked whether the prematurely aged appearance of emotionally stressed people was reflected in the genome of their cells.

Elissa Epel and colleagues used telomere length — which declines in older people — to compare the biological age of the blood cells of mothers that were caring for a sick child with that of mothers with a healthy child. They found a striking correlation between the duration of care giving and the accelerated shortening of telomeres. Mothers looking after a chronically ill child are “...subjected to the kind of grinding day-to-day stress that can wear anyone down”, sympathized Elizabeth Blackburn, one of the authors on the study “...and the longer their stress continued, the more it appeared they aged biologically” (San Francisco Chronicle, 30 November 2004). However, even those mothers with healthy children who felt emotionally stressed had shorter telomeres. And the blood cells in the high-stress group had aged by a staggering 9–17 years. “How we perceive the world can matter more than our objective reality”, says Elissa Epel (New Scientist, 29 November 2004) and she points out that this research is “...a dramatic example of the mind-body link” (San Francisco Chronicle, 30 November 2004).

But how do our emotions penetrate to the heart of our cells? “Right now,” says Dr Blackburn, “that is the black box, and that's what we're going to study next.” (The New York Times, 30 November, 2004.)