Intensive TV watching linked to brain shrinkage

Frequent television watching in middle age may be associated with accelerated brain aging and an increased risk of cognitive impairment. This was demonstrated by a study published in the journal Alzheimer's & Dementia (A&D).

Researchers analyzed data from approximately 1,700 adults (with a mean age of 53) who participated in the long-term American ARIC study. In the late 1980s, participants reported how often they watched television in their leisure time, and more than 20 years later they underwent brain MRI scans.

It turned out that people who watched television "very frequently" had smaller volumes in several brain regions compared to those who rarely or never watched it. The most notable changes affected structures associated with memory, as well as the frontal and occipital lobes.

In addition, television enthusiasts were more likely to show white matter damage — changes associated with brain aging, increased risk of stroke, dementia, and cognitive decline. The most pronounced changes were recorded by the researchers in men.

The association persisted even after accounting for other risk factors, including physical activity, smoking, alcohol consumption, diabetes, and body mass index.

No similar association was found in people who spent a lot of time sitting at work. On the contrary, they tended to show better condition of certain brain regions on average. The authors suggest that the issue is not sedentary behavior itself, but rather the nature of the activity: intellectual engagement during work may offset the negative effects of prolonged sitting.

The authors emphasize that the study does not prove a causal relationship; however, its findings suggest that for brain health, it is important not only to sit less but also to pay attention to what exactly a person is doing during that time.