Being obese and overweight can increase the risk of developing multiple health conditions including hypertension, cardiovascular disease, and type 2 diabetes. According to studies excess weight can also cause a chronic inflammatory state in the body.
Obesity is associated with this increased inflammatory state in which there is an increase in markers of inflammation and causes the increased risk of multiple health conditions.
A new study published in the journal JAMA Network Open, researchers form Canada determined the adiposity of more than 9,000 participants. They measure their body fat and visceral adipose tissue (VAT), which is the fat that predominantly sits around organs in the abdominal cavity.
The study assessed cognitive function using the Digital Symbol Substitution Test and the Montreal Cognitive Assessment. They also adjusted the scores for cardiovascular risk factors, educational level, and MRI detected vascular brain injury (associated with cognitive impairment).
The researchers found that a higher total body fat and VAT were each associated with changes in cardiovascular risk factors. Also, higher total BF was associated with greater MRI-detected vascular brain injury, largely associated with higher white matter hyperintensities and lacunar infarctions, and similar associations were observed for higher VAT and greater MRI-detected vascular brain injury.
The researchers found that higher total body fat and higher VAT were both significantly associated with lower DSST and MoCA scores. The association was greater on the DSST, which assesses processing speed, than on the MoCA, which is a multidimensional cognitive test.
Compared with those in the lowest quartile (25%) of adiposity, the performance of those in the highest quartile was equivalent to an additional 3 years of cognitive aging.
The study found that excess adiposity was a risk factor for reduced cognitive scores, independent of cardiovascular risk factors, educational level, and MRI-detected vascular brain injury.
Sonia S. Anand, et al. Evaluation of Adiposity and Cognitive Function in Adults. JAMA Netw Open. 2022;5(2):e2146324. doi:10.1001/jamanetworkopen.2021.46324