A new study from the University of Georgia found that sugar negatively impacts brain development in children. Kids consume sugar more than any other age group, despite warnings about high-sugar diets leading to health problems like obesity. Food companies directly target children in their ads and create sugary products to entice them. While parents could buy other foods for their children, processed foods’ affordability and convenience often outweigh the negatives.
Most people know that high sugar consumption can lead to obesity, heart disease, or diabetes, among other health problems. However, researchers have done few studies on how high-sugar diets in childhood impact brain development. The team wanted to focus their investigation on how sugar affected the hippocampus, a crucial area for learning and memory.
About the study
A University of Georgia faculty member led the research along with a University of Southern California research group. In a rodent model, the study showed that consuming sugary beverages daily during adolescence impairs learning and memory during adulthood. The team also found that changes in gut bacteria could be the culprit behind memory and learning difficulties. The study was published in the journal Translational Psychiatry on March 31.
They found that mice given the bacteria, called Parabacteroides, began to have memory problems during the study. This occurred even if they had never consumed sugar previously.
“Early life sugar increased Parabacteroides levels, and the higher the levels of Parabacteroides, the worse the animals did in the task,” said Emily Noble, assistant professor in the UGA College of Family and Consumer Sciences and first author of the study. “We found that the bacteria alone was sufficient to impair memory in the same way as sugar, but it also impaired other types of memory functions as well.”
How high sugar consumption impairs brain functioning and alters gut bacteria
The Dietary Guidelines for Americans, set by the USDA and U.S. Health and Human Services recommend limiting sugar. It proposes keeping sugar consumption at 10 percent or less of daily calories. However, the Centers for Disease Control and Prevention (CDC) found that Americans aged 9-18 greatly surpass this guideline. The majority of their daily calories come from sugary beverages, unfortunately.
The hippocampus helps with many cognitive functions and doesn’t develop fully until late adolescence. Because of this, researchers wanted to understand better how sugary diets could impact brain development and the gut microbiome.
What the study on high sugar diets and brain health revealed
Juvenile rats consumed their regular diet and an 11% sugar solution, identical to commercially sold sugary drinks. Then, the research team had the rats perform a memory task heavily dependent on the hippocampus. The task specifically measured episodic contextual memory. This is the ability to remember the context where the rats had previously seen a familiar object.
Not surprisingly, the rats given the sugar solution had a more difficult time completing the task.
“We found that rats that consumed sugar in early life had an impaired capacity to discriminate that an object was novel to a specific context, a task the rats that were not given sugar were able to do,” Noble said.
Researchers then had the rats perform another memory task that measured immediate recognition memory. This task didn’t involve the hippocampus and measured the rats’ ability to recognize something they had seen before. In this case, sugar didn’t impact the rats’ recognition memory.
“Early life sugar consumption seems to selectively impair their hippocampal learning and memory,” Noble said.
How a high sugar diet altered gut bacteria in the mice
Further investigation discovered that consuming large amounts of sugar resulted in more Parabacteroides in the gut microbiome. Over 100 trillion microorganisms live in the gastrointestinal tract and have a considerable impact on health.
Researchers wanted to identify exactly how the bacteria impacted memory and learning. To accomplish this, they increased levels of Parabacteroides in the microbiome of rats that had never consumed sugar. These rats showed difficulty completing both hippocampal-dependent and hippocampal-independent memory tasks.
“(The bacteria) induced some cognitive deficits on its own,” Noble said. He said that future research would focus on which specific pathways are involved in gut-brain signaling.
“The question now is how do these populations of bacteria in the gut alter the development of the brain?” Noble said. “Identifying how the bacteria in the gut are impacting brain development will tell us about what sort of internal environment the brain needs in order to grow in a healthy way.”
Other harmful effects of eating too many sweets
In addition to impacting brain development and altering gut bacteria, eating sweets can cause many other health problems.
- Leads to weight gain. Sugary beverages and snacks contain a lot of empty calories. According to Harvard University, the average American consumes about 22 teaspoons of added sugar daily, which equates to 350 calories. Foods with tons of sugar, like desserts, usually don’t have a lot of nutrients. By eating a more balanced diet and watching your calories, losing weight will become a lot easier.
- It can cause high blood pressure and metabolic disease. Those who consume 25% or more calories from added sugars daily have a threefold increased risk of dying from cardiovascular disease.
- Promotes moodiness. One study of 93,676 postmenopausal women found that diets high in sugar increased the risk of depression and mood disorders. Sugar can cause blood sugar dips and spikes, which may explain the results of this study.
Final Thoughts: University of GA study proves how sugar impairs brain development in kids
This rodent study found that juvenile rats who consumed sugar daily showed brain impairments even in adulthood. As young children get the majority of their calories from sugar, this is deeply concerning. The study revealed that rats given sugar in their typical diets had difficulty completing tasks associated with memory. They also had altered gut bacteria, though researchers still don’t know exactly how it affected their cognition.
However, experts around the world have sounded the alarm on sugar for decades because of its health dangers. Hopefully, companies will start making healthier alternatives so that children won’t be plagued with health problems in the future.