Sitting down too much may not be good for the brain according to a study of adults who’ve already reached middle age and above.
Researchers from University of California, Los Angeles (UCLA) noted that among 35 adults aging 45 to 75 without dementia, those who spent more time sitting in the day had greater thinning of the medial temporal lobe – the area of the brain responsible for making new memories.
Even combined with physical activity, it still didn’t make a difference according to the authors. You can find their study in the journal PLOS ONE.
The study also contributes to a growing body of evidence that too much sitting can increase risks of diabetes, heart disease, and other diseases – even if an individual is physically active.
Further research should be done to check if reducing sedentary behavior reverses the effect that they found.
But only a few studies about sitting and dementia risk exist. In their study background, the authors refer to literature that suggests physical activity might delay the development of Alzheimer’s and other dementias and can improve brain structure.
One explanation for this effect is that physical activity increases blood flow in the brain, which promotes the growth of nerve cells and prevents any deterioration in function and structure.
Sitting down may also impair brain even if you exercise
For the study, researchers also explored the links between medial temporal lobe thickness, exercise, and sitting time in 10 men and 25 women aged 45 to 75 who didn’t show symptoms of dementia.
Data on average hours spent every day and physical activity levels were gathered from detailed questionnaires, while medial temporal lobe thickness was measured from MRI scans of their brains.
When the data was analyzed, researchers found no significant correlations between levels of physical activity and medial temporal lobe thickness. They did find that more sedentary people had less medial temporal lobe thickness.
The study didn’t investigate the mechanisms behind prolonged sitting that might be bad for our brain, but authors suggest that “sedentary behavior may have deleterious effects on glycemic control.” This could in turn result to increased variability of blood sugar and lead to reduced blood flow in the brain. Reduced blood flow in the brain will then lead to brain health deterioration.