Linked from
The 30 pages that link to Caffeine, each with the reason it gives.
Sleep deprivationRelated: It may blunt sleepiness temporarily but does not replace lost sleep.
Camellia sinensisRelated: Tea leaves produce caffeine as a defense against herbivores.
Black teaRelated: Black tea delivers caffeine, though the amount varies with leaves and brewing.
Green teaRelated: Green tea contains caffeine, with amounts varying by leaf and preparation.
Energy drinkRelated: It is the main stimulant in most energy drinks.
WakefulnessRelated: It can temporarily support alertness without replacing sleep.
Kola nutRelated: This alkaloid contributes to the alerting effect of chewing kola nut.
Coffee (beverage)Related: It is one of coffee’s best-known active compounds.