Here’s What Watching TV in Midlife Does to Your Brain

Television has been mocked for wrecking society’s ability to think. Now, science has found evidence to support such worries.

People who watch moderate to high amounts of TV throughout the midlife years see greater declines in cognitive function and reduced gray matter volumes in their brains later in life, according to three studies recently presented at the American Heart Association’s 2021 Epidemiology, Prevention, Lifestyle & Cardiometabolic Health Conference.

Midlife was defined as ages 45 to 64. Cognitive function includes tasks like remembering, reasoning and problem-solving.

On a more positive note, there does not appear to be a link between viewing excessive amounts of TV at midlife and having a greater risk of dementia.

In one study, the researchers found that watching even moderate amounts of television during middle age is linked to declines in memory and ability to reason later in life. However, the researchers couldn’t say for sure that watching TV itself was directly responsible for this decline.

On the one hand, television viewing is recognized as a cognitively passive activity — it does not require much thought. However, the researchers also speculated that the decline could be tied to the fact that tuning in to television is a sedentary activity, and that too much couch time may be the source of harm to the brain.

In a press release, Dr. Mitch Elkind, chief of the Division of Neurology Clinical Outcomes Research and Population Sciences at Columbia University, says:

“It definitely rings true to me that both sedentary behavior and the things that go along with it like obesity and high blood pressure and diabetes could lead to a gradual accumulation of brain injury over time. The brain is also supplied by the blood vessels, and diseases of the heart and the blood vessels can lead to brain problems like cognitive decline and even dementia.”

If you watch too much TV and are concerned about the impact of all that sedentary time, the researchers suggest you:

• Get more activity. Elkind notes that a single bout of exercise each day might not be enough to protect the brain. “Overall, I would say the more movement, the better,” he says. “Try to get some activity in every hour, even if you have to set a little reminder to do it.”
• Substitute other activities for watching TV. Watching TV is a cognitively passive, sedentary behavior, meaning it does not require much concentration or thought or physical activity, says lead researcher Priya Palta, an assistant professor of medical sciences and epidemiology at Columbia University Vagelos College of Physicians and Surgeons. “This is in contrast to mentally active sedentary behaviors, like reading, that would be more cognitively stimulating or require more brain work,” she says.