Spread out flat, the gut lining covers around 32 square metres, about the floor space of a small studio apartment. It has an important job: to let nutrients through while keeping trillions of bacteria in the gut where they belong. In people with conditions like high blood pressure, diabetes and kidney disease, this barrier becomes “leaky”. Bacteria and the substances they produce slip into the blood, where the immune system treats them as invaders. The result is a constant, low-level burn of inflammation that damages blood vessels, the heart and kidneys. Over years, that damage can end in a heart attack, heart failure, or kidneys that stop working altogether.
He now leads the Gut Homeostasis in Cardiometabolic Health Laboratory at Edith Cowan University, where his team is developing better ways to measure gut leakiness in people, and testing which fibres best strengthen the gut barrier. The goal is to make the gut barrier a treatment target, addressed through diet alongside existing medicines.