Expanding Waistlines, Shrinking Brains?

Last year, a study found that people who were overweight in midlife had a higher risk of developing dementia later in life.  But a new study out of the University of California  finds an even stronger connection between weight and brain health…

In this study, brain scans of people in their 70s were examined, and compared to their weight – and a pattern developed.  The brains of the people who were overweight or obese appeared to be smaller, with much of the shrinkage in areas important for memory and planning.

Depending on how overweight they were, the difference made the senior’s brains appear 4-8 percent smaller, and 8-16 years older – a pretty significant difference!

None of the seniors showed symptoms of dementia, and the research doesn’t try to predict if they will develop cognitive problems.  But in general, smaller brain sizes are generally linked with declining brain health and function, making the finding worrisome.

Why  the link?

The researchers suggest that since obesity is  associated with clogged arteries, circulatory and heart problems, there might be issues with blood flow and oxygen supply to the brain.     Other scientists point out that obesity might not be the cause of the smaller brains, but a result;   the  same areas that shrank the most are the areas which regulate  eating behavior and metabolism.

In other words, if your brain is shrinking, you’re likely less able to control your weight.

But there’s good news, too.

Another study by the same team seems to show that exercise seems to protect the same brain regions negatively affected by obesity.    Though this particular research study is still unpublished, there are plenty of other peer-reviewed studies out there that show just how helpful physical exercise can be to brain health, encouraging new growth, restorative growth, and protecting existing brain cells.

So whether it’s a chicken or egg effect,  physical exercise appears to be a solution for the obesity/ brain atrophy connection.  Is it possible to be overweight and still brain-healthy if we actively exercise?  It’s too soon to know…. but  I think I’ll go for that extra walk this evening, just in case!

The more evidence piles up,  the clearer it seems to be that watching our weight and being physically active remains a crucial part of maintaining a healthy brain, and one that’s better prepared to ward off the effects of disease, hopefully  providing some level of Alzheimer’s and dementia prevention.