Caffeine (W) T-Shirt

This methylxanthine alkaloid is the single most widely consumed psychoactive drug in the world, is completely legal and unregulated nearly everywhere, and is also “generally recognized as safe” by the FDA. Its most commonly sought-after effect is central nervous system stimulation; it relieves drowsiness, improves performance, and gets you through the day. Its health benefits are mixed, as it can be used (as caffeine citrate) to alleviate breathing problems in premature babies as well as offer some protection against Parkinson’s disease and certain cancers, but can also cause cardiovascular health issues and of course a minor but notable drug dependence. Oddly, the FDA refers to it as a flavor additive for alcoholic drinks. Go figure.