Healthy Lifestyle Lengthens Telomeres?

Diet, exercise, and stress management may lengthen telomeres, a new study shows, though some scientists are skeptical.

Sep 18, 2013
Kate Yandell

U.S. DEPARTMENT OF ENERGY HUMAN GENOME PROGRAMLifestyle changes meant to increase physical fitness, lower stress, and alter diet were associated with lengthened telomeres in a small group of men, according to a study published yesterday (September 17) in The Lancet Oncology.

Telomeres are protective assemblages of DNA and protein at the ends of chromosomes. They guard the chromosomes from disintegration, and shorten with age. Telomere length is considered a marker of cellular health. “The more people changed their lifestyle, the more their telomeres got longer,” study coauthor Dean Ornish from of the University of California, San Francisco, told NPR.

Ornish and his colleagues recruited men with low-risk prostate cancer to either receive help changing their lifestyles or to be part of a control group and receive no lifestyle intervention. Members of the intervention group were taught to eat a low-fat diet high in fruits, vegetables, unrefined grains, and legumes, and received meals during the early months of the study. They engaged in moderate exercise, attended support groups, and were taught stress management techniques, including yoga and meditation.

At the end of a five-year period, 10 men from the intervention group and 25 from the control group provided blood samples, which the researchers used to measure the length of their telomeres. The researchers found significantly longer telomeres in members of the intervention group than in controls.

However, some scientists who were not involved in the study urged caution when interpreting its findings. Carol Greider of Johns Hopkins University told New Scientist that the researchers measured telomere length using a method of questionable accuracy.

Medical journalist Larry Husten pointed out in a Forbes article that the study drew its conclusions from a very small group of men and that, since there were so many interventions applied, it was unclear which ones had actually helped.

And Nir Barzilai of Albert Einstein College of Medicine said that it remains unclear whether longer telomeres led to better health or whether telomere length was simply a marker of better health. “Either you’re healthy, so you have longer telomeres. Or you have longer telomeres, and that's why you’re healthy,” he told NPR. “You can pick and choose what you believe in and make an argument.”