Parkinson’s is often framed as a brain-first disorder, but some of its earliest changes unfold in the gut. This episode unpacks a global metagenomic analysis showing that two surprisingly ordinary microbial compounds, ones most people consume every day, quietly disappear in Parkinson’s. When these pathways vanish, gut defenses weaken, protective metabolites fall, and enteric neurons may become vulnerable to the toxins that start pathology long before tremors appear. The goal: reveal how the l...