18 October 2016 - MedicalXpress - BMI is linked to brain function
There are plenty of reasons it's important to maintain a healthy weight, and now you can add one more to the list: It may be good for your brain.
Researchers from the University of Arizona have found that having a higher body mass index, or BMI, can negatively impact cognitive functioning in older adults.
How? They say inflammation is to blame.
"The higher your BMI, the more your inflammation goes up," said Kyle Bourassa, lead author of the study, which is published in the journal Brain, Behavior and Immunity. "Prior research has found that inflammation—particularly in the brain—can negatively impact brain function and cognition."
Previous studies also have linked higher BMI—an index of body fat based on height and weight—to lower cognitive functioning. But how and why the two are connected was far less clear.
"We saw this effect, but it's a black box. What goes in between?" said Bourassa, a UA psychology doctoral student. "Establishing what biologically plausible mechanisms explain this association is important to be able to intervene later."
Bourassa and his co-author, UA psychology professor David Sbarra, analyzed data from the English Longitudinal Study of Aging, which includes over 12 years' worth of information on the health, well-being and social and economic circumstances of the English population age 50 and older.
Using two separate samples from the study—one of about 9,000 people and one of about 12,500—researchers looked at aging adults over a six-year period. They had information on study participants' BMI, inflammation and cognition, and they found the same outcome in both samples.