Scientists uncover alarming fact about fast food

Researchers from the University of North Carolina School of Medicine have identified the mechanism by which fatty foods and fast food negatively affect brain function, *New Atlas* reports.

“We knew that poor diet harms the brain, but we did not expect this specific group of cells to be so vulnerable. What surprised us most was how quickly they change activity when glucose availability decreases — and how this alone was enough to disrupt memory function,” the researchers explained.

The study focused on cholecystokinin-positive (CCK) interneurons, according to *RIA Novosti*. These cells act as “brakes” in the hippocampus — the brain region responsible for memory. Their role is to maintain the rhythmic activity of excitatory pyramidal neurons, the “workhorses” of the hippocampus. When pyramidal neurons become overactive, information processing turns into chaotic flow. However, overstimulation of CCK-positive interneurons, in turn, can suppress pyramidal neuron activity, depriving the hippocampus of the ability to form and consolidate new memories.

In mouse experiments, researchers found that just four days of a high-fat diet reduced glucose availability in the brain. This triggered excessive activity of CCK-positive interneurons and impaired memory in behavioral tests — even before weight gain or symptoms of diabetes appeared.

A key player in this process was the protein pyruvate kinase M2 (PKM2), which regulates the amount of glucose used by cells. When glucose was deficient, the balance was disrupted, pushing CCK-positive interneurons into “overdrive.”

Although the study was conducted in animals, the scientists emphasize that long-term consumption of fatty foods, including fast food, significantly increases the risk of developing serious conditions such as dementia and Alzheimer’s disease.