Study Suggests Overweight People Have Smaller Brains

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Carrying excessive body fat not only puts your health at risk, but it also puts a big strain on your brains, according to a study published yesterday.

CNN reports that a study in the journal Neurology suggests if you’re a bit chunky around the middle, then the chances are the gray matter volume in your brain has diminished somewhat.

Gray matter is important because it contains the lion’s share of your brain’s 100 billion nerve cells.

The study in question measured the body mass index (BMI) and waist-to-hip ratio of 9,652 people in the UK. One in five members of the study were found to be obese

The participants also had their brain volume scanned via an MRI. After accounting for other factors which could reduce gray matter volume such as smoking and high blood pressure, the researchers found that those with above average numbers on both BMI and waist-to-hip ratio had the lowest gray matter volume.

The study showed that excess weight was also connected with shrinking of the areas of the brain linked to motivation and reward.

Study author Mark Hamer explained that “previous studies have shown associations between gray matter atrophy and risk of developing dementia. In this study, the reductions in brain size increase in a linear fashion as fat around the middle grew larger.”

Hamer also stated that it was unclear “if abnormalities in brain structure lead to obesity or if obesity leads to these changes in the brain.”

Assistant professor in the Department of Psychiatry and Behavioral Sciences at the Stanford University School of Medicine, Cara Bohon, said that the study’s findings are “not particularly new or surprising.”

However, she did indicate that the amount of participants involved seemingly proves what many scientists have hitherto guessed – being fat is more damaging than we once realized.

An overweight woman on the beach.
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Bohon said, “one particularly interesting finding is that, among individuals with obesity, those with greater waist-to-hip ratio (a marker of visceral fat around the abdomen), showed even lower gray matter volume.

“Because the cause of a connection between brain volume and obesity is still unclear, perhaps something may be causing both. For example, if there are nutritional factors impacting brain volume, these same nutritional factors could be a direct cause of obesity.”

Hamer believes the research will assist scientists in continued research into how obesity relates to the risk of neurodegenerative disease.

He said, “obesity can have a detrimental impact on a wide range of health parameters. People should strive to maintain normal body weight.”

In other words, don’t pile on the pounds because it may be more costly than you think.