No one actually thought sitting around on the couch would help your overall health, of course. But this is an interesting development: researchers at King’s College London found that people who lead a sedentary lifestyle age faster than their more active counterparts in terms of risk of heart disease, type 2 diabetes, cancer, high blood pressure, etc. and—here’s the kicker—their DNA actually aged more quickly, too.
Here’s the skinny:
Lynn F. Cherkas, Ph.D., of King’s College London, and colleagues studied 2,401 white twins, administering questionnaires on physical activity level, smoking habits and socioeconomic status. The participants also provided a blood sample from which DNA was extracted. The researchers examined the length of telomeres–repeated sequences at the end of chromosomes–in the twins’ white blood cells (leukocytes). Leukocyte telomeres progressively shorten over time and may serve as a marker of biological age.
Telomere length decreased with age, with an average loss of 21 nucleotides (structural units) per year. Men and women who were less physically active in their leisure time had shorter leukocyte telomeres than those who were more active.
[...]
“The mean difference in leukocyte telomere length between the most active [who performed an average of 199 minutes of physical activity per week] and least active [16 minutes of physical activity per week] subjects was 200 nucleotides, which means that the most active subjects had telomeres the same length as sedentary individuals up to 10 years younger, on average.”
Now as a follow-up editorial by a different aging researcher says, people with sedentary lifestyles differ from active people in lots of ways, and while the researchers did control for many variables, it’s quite possible that they missed something important. But this DNA connection is fascinating—I bet we’ll be seeing more and more studies like this as we strive to learn more about how our health affects our DNA, and vice versa.
Tags: active, aging, DNA, leukocyte telomeres, physical activity, sedentary
