A new small study in rats found that drinking sugary beverages may result in memory issues down the line.
"It's no secret that refined carbohydrates, particularly when consumed in soft drinks and other beverages, can lead to metabolic disturbances," said study author Scott Kanoski, of the University of Southern California. "However, our findings reveal that consuming sugar-sweetened drinks is also interfering with our brain's ability to function normally and remember critical information about our environment, at least when consumed in excess before adulthood."
In the study, both adult and adolescent rats were given daily access to sweetened beverages that mirrored high fructose corn syrup or sucrose sugar concentrations found in common soft drinks.
Studies have linked eating sugar and carbohydrates a raft of maladies, like obesity and diabetes, as well as one which linked it to reduced brain function in the elderly. But this study isolated sugar as consumed specifically in a beverage, and focused on adolescents, whose hippocampus is still developing.
The findings are being presented at the Annual Meeting of the Society for the Study of Ingestive Behavior (SSIB), and are preliminary. The researchers plan to explore whether the soda is causing inflammation in the brain's hippocampus, which is the region of the brain involved in memory and learning.
"This could," said Kanoski, "result from peripheral insulin resistance, which was present in the adolescent rats that consumed SSB [sugar-sweetened beverages], and has been previously linked with neuroinflammation." He adds that it's possible that sugary drink consumption may also degrade the blood-brain barrier, which has been hinted at in previous studies, but needs to be confirmed.
Though the research has not been done in humans, it's part of a growing body of work looking at the risks of soda.