TV might actually be rotting our brains. Watching television for extended periods of time could increase the risk of dementia and Alzheimer’s disease, new research says. To combat this danger, experts recommend taking breaks from binge-watching and engaging in more mentally stimulating activities.
Your brain on TV
Frequent TV watching in midlife was associated with reduced volume in the parts of the brain vulnerable to Alzheimer’s disease, according to a study published in Alzheimer’s & Dementia. The diminished brain systems include those associated with memory and cognition as well as executive functioning. More surprisingly, the brain volume reduction was not tied to sedentary behavior but specifically to watching TV. “People whose jobs involved sitting for much of the day tended to have healthier-looking brains,” said ScienceAlert. Also, “when the researchers accounted for differences in overall physical activity, that didn’t seem to impact the outcome.”
The results also showed that men were particularly vulnerable to these brain changes. “This could be because men and women accumulate sedentary time differently,” Natan Feter, a biological scientist and the lead author of the study, said to ScienceAlert. “Women may interrupt their sitting more often” or “biological differences in how the brain responds to prolonged sedentary behavior” may be to blame. In general, “women tend to prefer TV programming in shorter chunks, though they spend more time watching overall,” said ScienceAlert. By contrast, “men’s preferences for watching sports and movies” mean they are are “more likely to spend long, uninterrupted periods on the couch.”
Researchers analyzed a sample of 1,712 adults with an average age of 53 years who did not have a diagnosis of dementia when the research began. Between 1987 and 1989, “participants completed a detailed physical activity questionnaire during an in-person interview,” where they reported “how often they watched television during their leisure time,” as well as “answered specific questions about how often they sat down during their work hours,” said PsyPost. Between 2011 and 2013, the participants underwent an MRI of their brains.
The study “shows an association, not a cause-and-effect relationship” between TV and dementia, Feter said to Healthline. The researchers also “relied on self-reported data for TV consumption, which can be less precise than timed tracking,” said a news release about the study.
Beyond the screen
“For years, we’ve focused on how much people sit,” David Raichlen, a professor of biological sciences and anthropology at the USC Dornsife College of Letters, Arts and Sciences and the senior author of the study, said in the news release. But these findings “suggest we should also pay attention to what they’re doing while they’re sitting.” For example, working from home, while sedentary, is more “intellectually stimulating” compared to watching TV, said the release.
Because TV watching appears to specifically affect the brain, “we might eventually see a different approach to health guidance around sedentary activities,” said the release. “Rather than just directing their patients to move more, for example, physicians might recommend they reduce television time and add cognitively engaging activities for when they do sit.” Activities like “puzzling, crafts and even texting, which require your brain to work while you are sitting might also change how much sitting negatively impacts your brain,” said ScienceAlert.
“The goal is not to eliminate passive rest,” Dung Trinh, a doctor at the MemorialCare Medical Group and the chief medical officer of Healthy Brain Clinic in Irvine, CA, said to Healthline. It is to “build more cognitively engaging moments into the day.”