A new study has found a link between the breadth of your belly and the size and shape of your brain, as findings, published in the medical journal Neurology, showed that people who are too heavy, especially around their middle, have shrunken gray matter volume in their brain. Gray matter contains most of your brain’s 100 billion nerve cells, while white matter is filled with nerve fibers that connect the brain regions.
The Scientists at the University College London and Loughborough University in the UK reached these conclusions by studying the UK Biobank, a vast stockpile of data on individuals’ genetics and health.
They looked at almost 9,652 people in the UK, with an average age of 55, accounting for all kinds of other factors that could potentially sway the results, such as age and how physically active they were. Measuring the body mass index (BMI) and the waist-to-hip ratios of its participants, the research found that those with higher ratios of both criteria had the lowest brain volume.
In fact, the difference was substantial: people with high BMI and a high waist-to-hip ratio had an average gray matter brain volume of 786 cubic centimeters, while healthy weight people had an average of 798 cubic centimeters. People in the middle, with a high BMI but without high waist-to-hip ratio, had an of 793 cubic centimeters.
The white matter, however, did not appear to be affected by obesity. “While our study found obesity, especially around the middle, was associated with lower gray matter brain volumes, it’s unclear if abnormalities in brain structure lead to obesity, or if obesity leads to these changes in the brain,” study author Dr Mark Hamer said in a statement.
“We also found links between obesity and shrinkage in specific regions of the brain. This will need further research but it may be possible that someday regularly measuring BMI and waist-to-hip ratio may help determine brain health.”
Meanwhile, the connection between reduced brain volume and abdominal fat could suggest that inflammation and vascular factors may be at work.