When Coffee Works Against You: The Neurobiology of Caffeine-Induced Fatigue
For a meaningful subset of the population, caffeine does not reliably deliver the alertness it promises — and the reasons are rooted in neurobiology, not willpower. Understanding why certain individuals experience pronounced fatigue or energy crashes after caffeine consumption requires examining receptor dynamics, genetic variation, and the often-overlooked role of inhibitory neurotransmitters. This article unpacks the science behind one of the most counterintuitive phenomena in energy physiolog