Scientists found evidence that high levels of body fat among people who are obese can significantly alter the brain's form and structure.
In particular, a large new study linked high levels of body fat with smaller volumes of gray matter, or the tissue that contains nerve cells, in the brain. Moreover, researchers found that obesity's effect on the brain might be more significant among men than women.
Researchers Links Obesity To Brain Shrinkage
Researchers from Leiden University Medical Center in Netherlands analyzed gray and white matter in the brains of about 12,000 people using MRI results provided by the UK Biobank. They found that there is a significant link between higher levels of fat all over the body and smaller volumes of the important structures of the brain, including gray matter.
The findings confirm previous research that associated body fat, particularly in the belly, with lower brain volumes. Obesity has also been linked to a higher risk of developing dementia among other diseases.
The researchers also found that men who have higher levels of body fat are likely to have smaller volumes of gray matter in the brain. For women, the result of a higher percentage of total body fat affected the globus pallidus.
"Interestingly, we observed that these associations are different for men and women, suggesting that gender is an important modifier of the link between fat percentage and the size of specific brain structures," said Ilona A. Dekkers, the first author of the study published in the journal Radiology.
Obesity Is Bad For The Brain, Too
The researchers clarified that the study only demonstrated a link between obesity and bran shrinkage. It does not prove that obesity can change the brain or cause brain shrinkage. The ramifications of the findings are also currently unknown.
However, the study adds to the growing number of evidence claiming that obesity can significantly impact the brain.
"For future research, it would be of great interest whether differences in body fat distribution are related to differences in brain morphological structure," explained Hildo Lamb, director of the Cardio Vascular Imaging Group at Leiden University and the senior author of the study. "[V]isceral fat is a known risk factor for metabolic disease and is linked to systemic low-grade inflammation."
According to the Centers for Disease Control and Prevention, obesity affects 93.3 million adults in the United States in 2016.