Usually, when your tongue goes blue it's because you ate some funky candy - or you're seriously sick. With our most recent guest, however, it's a sign that you've taken a supplement the biohacking world is going crazy for: Blue Cannatine.

This week, Josh interviews Dr Scott Sherr; internal medicine physician, practitioner of Health Optimisation Medicine, and specialist in Hyperbaric Oxygen Therapy. Listen in as the two discuss how Dr Sherr helps optimise the health of his patients, the world of troscriptions, and how he hacks brain performance.