The Vagus Nerve controls various bodily functions, such as digestion, heart rate, and mood regulation. Recently there's been a surge in alternative therapies that claim to stimulate the Vagus Nerve, including icing, breathing exercises and meditation. In this video, I test the most popular TikTok trend, icing, based on the mammalian dive reflex. We explore the science behind VNS, the latest therapies, and what personalised medicine could look like in the future.