Sugar-Sweetened Beverages Consumed During Adolescence Impairs Memory

Daily consumption of sugar-sweetened beverages severely impairs memory among adolescents, a new study reveals.

Sugar-sweetened beverages are listed as the leading contributors to the obesity epidemic in the U.S. They are made of energy-containing sweeteners like fruit juice concentrates, corn syrup and sucrose. The intake of these empty calories and high sugar leads to the development of type-2 diabetes and obesity. They contribute to 48 percent of added sugar in our diet.

In this study, the researchers found that daily intake of beverages sweetened with high-fructose corn syrup or sucrose leads to reduction in the ability to learn and retain information. This risk is higher if the consumption is more during adolescence.

The researchers conducted an experiment on adult and adolescent rats. These rats were given access to sugar-sweetened beverages daily. The beverages replicated the concentration of sugar present in soft drinks.

They noticed that the adult rats who consumed sugar-sweetened beverages continuously for a month did well in tests of cognitive function. However, when the adolescent rats consumed the sugar-sweetened beverages, their memory and learning ability was impaired as they performed poorly in the tests.

The lead author, Dr. Scott Kanoski, from the University of Southern California said, "It's no secret that refined carbohydrates, particularly when consumed in soft drinks and other beverages, can lead to metabolic disturbances. 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."

Apart from triggering memory impairment in the adolescents, the sugar-sweetened beverages also caused inflammation in the hippocampus, the region of the brain that regulates learning and memory functions.

"The hippocampus is such a critical brain region for memory function", said Kanoski. "In many ways this region is a canary in the coal mine, as it is particularly sensitive to insult by various environmental factors, including eating foods that are high in saturated fat and processed sugar."

Earlier, health experts recommended that replacing water for such beverages could lower the consumption of empty calories and improve nutrition.

The research will be presented at the Annual Meeting of the Society for the Study of Ingestive Behavior (SSIB).