The protective endcaps of chromosomes that affect how quickly cells age, telomeres are combinations of DNA and proteins that protect the ends of chromosomes and help them remain stable. Telomere shortening is associated with a weakening of structural integrity, and is thought to be a mechanism of aging.
Eli Puterman, from the University of California/San Francisco (UCSF; California, USA), and colleagues examined three healthy behaviors, namely – physical activity, dietary intake and sleep quality – over the course of one year in 239 post-menopausal, non-smoking women. The women provided blood samples at the beginning and end of the year for telomere measurement and reported on stressful events that occurred during those 12 months.
In women who engaged in lower levels of healthy behaviors, there was a significantly greater decline in telomere length in their immune cells for every major life stressor that occurred during the year. Yet women who maintained active lifestyles, healthy diets, and good quality sleep appeared protected when exposed to stress – accumulated life stressors did not appear to lead to greater shortening.
Observing that: “Women who maintained relatively higher levels of health behaviors (1 standard deviation above the mean) appeared to be protected when exposed to stress,” the study authors submit that: “This finding has implications for understanding malleability of telomere length, as well as expectations for possible intervention effects.”