Experts at the University of Southampton have launched a new science project, the 'Blue Poo Test', to better understand the link between the gut and the brain. The research team is asking thousands of people across the UK to participate.
The test involves eating a muffin baked with edible blue food colouring and tracking how quickly it is digested. Once a participant's poo turns blue, they are asked to play five-minute online brain games designed to measure problem-solving skills and decision-making under pressure.
Professor Jonathan Swan, a Professor of biomolecular medicine at the University of Southampton, stated that while everyone's gut works at a different speed, its implications for brain function are not yet fully understood. The project aims to determine if a faster gut transit means a sharper mind or if slower digestion changes how people think.
The scientists hope to map how gut-digestion times vary across age groups, sexes, and regions, and how these variations correlate with brain performance. The research is open to individuals aged five to nearly 100 years old and is funded by the Biotechnology and Biological Sciences Research Council (UK Research and Innovation).