Sitting and the Aging Brain

We spend much of our day sitting. Whether it’s driving from point a to point b, switching channels with the remote control, or tapping away at our keyboards or phones; our bodies spend an inordinate amount of time bent at the hips and at the knees, reaching forward.

While the big news a few years ago was that sitting for most of your day puts you at more risk for disease than smoking; the research into living a sedentary lifestyle has gotten more nuanced. Two recent studies show that how much time we spent seated has a significant effect on our genes.

The first study, published in The Journal of Alzheimer’s Disease, tracked over 1,600 older adults over 5 years. All of them were dementia-free at the beginning of the study. They found that participants who were not at risk of developing dementia due to genetic predisposition could significantly decrease the likelihood of developing it in the future by being more active. Sedentary individuals had a much higher incidence of dementia by the end of the study. Jennifer Heisz, PhD, who co-authored the study said, “Given that most individuals are not at genetic risk, physical exercise may be an effective prevention strategy.” While researchers aren’t willing to offer a prescriptive exercise that offers the greatest protective benefit, it’s safe to assume that any kind of movement that involves not just sitting still is worth it. If you enjoy the movement, even better.

Genetic research shows that telomere length correlates with aging. Telomeres are the end caps of our DNA, and damaged or shortened telomeres mean more disease and faster aging. A study found in the American Journal of Epidemiology examined the connection between time spent sitting and telomere length.

Nearly 1,500 white and African-American women, with an average age of 79, kept track of their own movement and were also tracked by a device worn on their hip designed to measure physical activity. The results showed that women who sat for more than 10 hours daily had a biological age of eight years older than their chronological age. It turns out that the exercise doesn’t have to be extreme or lengthy; researchers found that even 30 minutes per day of exercise offered a protective effect for telomere length.

I have no doubt that research will continue to explore the mechanisms between how active we are in our lives, and how that affects both our bodies and our brains. Rather than waiting for a prescription from our doctor as to what is the best type of movement, we can do ourselves a favor by continuing to find ways to move that we enjoy, and spending more time doing them, and less time sitting.

Read more from Kalia Kelmenson.