Junk food linked to reduced brain function and memory, study finds
It’s widely known that diets high in saturated fat and refined sugar can lead to obesity, heart disease, and certain cancers. But a new study reveals these unhealthy habits also impair brain function, especially memory. Dr. Dominic Tran from the University of Sydney, lead author of a paper in the International Journal of Obesity, explains that high-fat, high-sugar diets aren’t just a problem for older adults—t...hey also affect children, teenagers, and young adults. In fact, the damage to brain function often begins long before any noticeable weight gain occurs.
The hippocampus, a seahorse-shaped structure located deep within the brain’s temporal lobes, plays a key role in memory formation and spatial navigation. When individuals consume diets rich in saturated fats—such as processed meats and fast food—it leads to neuroinflammation, which directly harms the hippocampus. Professor Frédéric Meunier of the University of Queensland emphasizes that this inflammation weakens the brain’s ability to create and recall memories.
Other effects include reduced levels of neurotrophic factors, which are essential for building neurons and supporting memory function. Diets high in fat can also contribute to insulin resistance in the brain, further damaging cognitive performance. While much of this research began with rodents, recent experiments on humans—including virtual maze tests—have confirmed similar results. Participants who ate less junk food showed better memory and spatial awareness.
The good news? These effects appear to be reversible. Healthier diets can restore hippocampal function and improve memory, even in early adulthood.