how long does caffeine stay in your system?
Scientifically, caffeine resides longer in womenâs system than that of men. The average half-life of caffeine in healthy humans persists for 4.9 hours. In men, typically residing between 5 to 9 hours, after the consumption of caffeine. Surprisingly, smokers are at benefit here, because it is flushed out sooner in them in comparison to the non-smokers by 30%-50%.