<P> Caffeine is also a common ingredient of soft drinks , such as cola , originally prepared from kola nuts . Soft drinks typically contain 0 to 55 milligrams of caffeine per 12 ounce serving . By contrast , energy drinks , such as Red Bull , can start at 80 milligrams of caffeine per serving . The caffeine in these drinks either originates from the ingredients used or is an additive derived from the product of decaffeination or from chemical synthesis . Guarana , a prime ingredient of energy drinks , contains large amounts of caffeine with small amounts of theobromine and theophylline in a naturally occurring slow - release excipient . </P>
where does caffeine come from in energy drinks
ingredients used additive derived from the product of decaffeination or from chemical synthesis