Study Reveals Link Between Diet Quality and Cognitive Performance - Video

New research links fatty, sugary diets to impaired brain function. The findings build on a growing body of evidence showing the negative impact of high-fat, high-sugar (HFHS) diets on cognitive ability, adding to their well-known physical effects. Findings are published in the International Journal of Obesity. The research is the first to test in humans the relationship between high-fat, high-sugar diets, particularly those high in refined sugar and saturated fat, and first-person spatial navigation. Spatial navigation is the ability to learn and remember a path from one location to another, a process that can approximate the health of the brain's

hippocampus.

The research found that high-fat, high-sugar diets have a detrimental effect on some aspects of cognitive function. It is likely that those effects center on the hippocampus, the brain structure important for spatial navigation and memory formation, rather than acting across the entire brain.

The research team recruited 55 university students aged between 18 and 38. Each participant completed questionnaires capturing their intake of sugary and fatty foods. They also had their working memory tested in a number recall exercise, and their body mass index (

BMI) recorded.

The experiment itself required participants to navigate a virtual reality maze and locate a treasure chest six times. The maze was surrounded by landmarks that participants could use to remember their route. Their starting point and the location of the treasure chest remained constant in each trial.

If participants found the treasure in less than four minutes, they continued to the next trial. If they failed to find the treasure in this time, they were teleported to its location and given 10 seconds to familiarise themselves with that location before the next trial.

A seventh trial removed the treasure chest from the virtual maze but asked participants to find and mark its former location based purely on memory. Those with lower levels of fat and sugar in their diets were able to pinpoint the location with a higher degree of accuracy than those who consumed these foods multiple times a week.

Reference: https://www.sydney.edu.au/news-opinion/news/2025/04/21/high-fat-high-sugar-diets-impact-cognitive-function.html