A new study indicates that what you do while sitting may be more important than simply how much time you spend seated.
Researchers analyzed data from approximately 1,700 American adults.
Participants reported, among other things, how often they watched TV during their leisure time. More than 20 years later, they underwent brain scans.
The findings were published in the journal Alzheimer's & Dementia and were also reported by ScienceDaily.
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Mental tasks may make a difference
The study found that people with sedentary jobs did not experience the same brain changes as those who frequently watched TV.
According to the researchers, many office jobs require concentration, planning, and problem-solving.
As a result, mentally stimulating activities may affect the brain differently from passive TV viewing.
However, the researchers emphasized that more studies are needed, partly because participants self-reported their TV habits, and brain scans were not available at the beginning of the study.
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Poorer brain function
People who reported watching TV very frequently during midlife were later found to have smaller brain regions associated with memory, decision-making, and vision.
They also showed more signs of changes in the brain's white matter, which has previously been linked to cognitive decline and dementia.
The association remained even after the researchers adjusted for factors including physical activity, smoking, alcohol consumption, diabetes, and body mass index (BMI).
The researchers also found that the results appeared to be particularly pronounced among men, but they stressed that further research is needed to understand why.
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