Link: https://www.verywellmind.com/prevent-brain-shrinkage-2795016

Effects of a Shrinking Brain
Brain shrinkage can play a role in age-related declines in cognitive abilities. As they get older, people may experience a reduction in their abilities related to:

• Episodic and working memory
• Processing speed
• Spatial reasoning

Brain shrinkage is sometimes referred to as cerebral atrophy or brain atrophy. Atrophy refers to a loss of cells. When this loss occurs within the brain, it means a loss of neurons and their connectors.2

A reduction in brain connectivity can lead to delirium, which is more common in elderly patients than their younger counterparts, even potentially progressing to dementia.3 Thus, finding ways to counteract this effect may help preserve cognitive function later in life.

Other aging-related brain changes can include:

• Decreases in brain mass
• Loss of connections between neurons
• Changes in the neurotransmitter systems that communicate information in the brain and body

Brain Shrinkage Causes
What causes the brain to shrink or atrophy as we get older? There are a couple of factors to consider.

Low Fitness Levels

Researchers from the Boston University School of Medicine found that people with poor physical fitness in their 40s have significantly lower brain volumes by the time they reach age 60.4 Experts consider this decrease in brain volume a sign of accelerated brain aging.

The study reviewed exercise data from more than 1,200 adults who were around the age of 40, all of whom were part of the larger Framingham Heart Study. When these participants were given MRI scans 20 years later, those who were less fit in midlife had much lower levels of brain tissue later on.

Vascular Damage

The researchers from Boston University also found that people with low fitness levels had a much higher rise in diastolic blood pressure after just a few minutes on a treadmill, even when moving at a slow pace. It was these people who were more likely to have reduced brain volume at age 60.

Fluctuations in blood pressure can damage small vessels in the brain that are vulnerable to such changes. Vascular damage in the brain can then contribute to structural changes and cognitive losses.

The researchers in this study were interested in looking at how these dramatic blood pressure changes could contribute to future brain structure changes. They found that those who had lower fitness levels in midlife did worse on cognitive tests at age 60 than those who had been fit during their 40s.

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Never let a report like this prevent you from starting an exercise routine, regardless of your age. Don't use this as an excuse to give up. Exercise is always beneficial.