The human gut microbiome (the microbes in the human gut) is a recently discovered ‘hidden organ’ which plays a crucial role in human health and disease. Only in recent years have scientists discovered the incredible control that this microbial organ has over our health, from our weight, to cholesterol levels, even to brain health. However, through modern lifestyles and medical practices, such as westernised diets, c-sections and overuse of antibiotics, we have begun to wage war on our microbial friends. By altering and destroying our microbiomes we have primed ourselves for modern plagues of obesity, asthma, diabetes and even mental illness. In this talk, Ruairi will give some food for thought about the incredible relationship between our belly and brain and between microbe and man. More importantly, discover how we need to change our approach to food and health so that we can restore our relationship with our microbes to benefit physical and mental health, globally.