Sitting and memory loss – what do the two have to do with each other?

In recent years, studies have noted various health issues associated with sitting too much, from diabetes to heart disease. This holds true even among those who regularly exercise.

But the latest research finds that among people middle-aged and older, an area of the brain crucial for learning and memory thins out significantly when they sit for prolonged periods of time.

The medial temporal lobe and the sub regions that make it up are plumpest when people stand and move frequently, according to the first-of-its-kind study. This structure naturally loses volume with age, but the study points to a strong correlation between too much sitting and memory loss.

The findings are based on interviews and tests conducted by researchers at the University of California, Los Angeles Semel Institute and its Center for Cognitive Neurosciences. They observed 35 cognitively healthy people between the ages of 45 and 75, questioning their physical activity patterns and completing MRIs on their brains. From there, the researchers related the participants’ self-reported sitting and exercise time to the thickness of the medial temporal lobe.

Every additional hour of average daily sitting time meant a 2% decrease in the brain structure, according to the study. That means that someone who sits for 15 hours a day would have a medial temporal lobe that’s 10% thinner than someone of the same age who sits for 10 hours a day.

However, the study indicates no correlation between exercise habits and the thickness of this brain structure. This is especially noteworthy since other research suggests better memory among those who work out more.

“Of course, we need larger samples and better ways to measure sedentary behavior,” biostatician and quantum chemist at UCLA and study leader Prabha Siddarth said. “But if you’re sitting for long periods of time, it seems that factor – not physical activity – becomes the more harmful or more significant measure of your fitness. Even for people who are physically active, sitting a lot seems to be bad for your brain.”

For more information about the study and its implications related to sitting and memory loss, please click here.