Extra weight may be aging your brain faster than you think
A major 24-year study involving more than 8,200 adults suggests that excess body weight may accelerate brain aging, leading to faster declines in memory, concentration, and decision-making skills. The connection was particularly strong among people over 65, raising concerns about the long-term effects of obesity on brain health.
Key points
- A University of Georgia study links higher BMI to faster declines in memory, overall cognitive performance and executive functioning.
- The analysis tracked more than 8,200 adults over age 50 for 24 years, with the strongest effects seen in adults older than 65.
- Lead author Suhang Song says managing weight could significantly lower the rate of cognitive decline within just two years.
A higher body mass index may speed up cognitive decline, according to new research from the University of Georgia. The study suggests that people carrying excess weight could see memory and thinking abilities deteriorate more quickly as they age.
Researchers analyzed data from a nationally representative study that followed more than 8,200 adults over age 50 for 24 years. They found that people with higher BMI experienced faster declines in memory, overall cognitive performance and executive functioning, the abilities used for concentrating, planning, organizing tasks and regulating emotions.
How the link appeared
Each one-point increase in BMI was tied to a faster rate of cognitive decline, indicating that even small differences in body weight could matter over time. The association was strongest in the study's eighth year, and adults older than 65 showed the most pronounced effects.
The study does not establish that excess weight directly causes cognitive decline. Researchers suggest several biological processes could help explain the connection, including inflammation, impaired blood circulation and insulin resistance, which together could raise the likelihood of cognitive impairment, Alzheimer's disease and other forms of dementia.
There are no cures for dementia, which is why it is critical to identify and address any modifiable risk factors we can find to prevent it.
— Suhang Song
Weight as a risk factor
The researchers say managing body weight may help slow cognitive decline, with possible benefits appearing within two years. Song, the study's lead author and an assistant professor at the University of Georgia's College of Public Health, said this makes BMI one of the most easily modifiable risk factors in aging well.
The findings come as obesity is widespread in the United States. According to the Centers for Disease Control and Prevention, about two in five Americans meet the criteria for obesity when BMI is used as the sole measure, a figure that rises to 75% under broader criteria. More than 7 million Americans live with dementia, and researchers expect that number to double by 2050. The research was published in the Journal of Neurology.
