Caffeine is the world's most popular drug, and most of us run on it without knowing how it works. This short course explains the real mechanism — caffeine blocks tiredness rather than adding energy — why its long half-life means afternoon coffee can cost you sleep, how tolerance and withdrawal build, how much caffeine is in what (and how much is safe), and what caffeine genuinely does and doesn't do. Evidence-graded; educational, not medical advice.
Caffeine is the world's most popular drug, and most of us run on it without knowing how it works. This short course explains the real mechanism — caffeine blocks tiredness rather than adding energy — why its long half-life means afternoon coffee can cost you sleep, how tolerance and withdrawal build, how much caffeine is in what (and how much is safe), and what caffeine genuinely does and doesn't do. Evidence-graded; educational, not medical advice.
