Neurotransmitters as Body‑Wide Communicators

Molecules commonly labeled 'neurotransmitters' (like dopamine, GABA, glutamate, oxytocin) operate outside the nervous system — in gut cells, muscles, kidneys, immune tissues and even in microbes and plants — mediating physiological processes that affect health. Reframing them as general 'chemical biomediators' reveals evolutionary continuity and suggests that diet, drugs, and the microbiome can alter their systemic roles. — This reframing shifts how medicine, public‑health guidance, and drug regulation should evaluate side effects and therapeutic targets beyond the brain.