You go to bed at 8pm??

It might seem like that but I’ve seen it recommended by doctors more than once. Caffeine stays in our system longer than most expect.

According to the FDA, the half-life of caffeine — the time it takes for the starting amount of the substance to reduce by half — is between four and six hours. This means that up to six hours after drinking a caffeinated beverage, half of the caffeine you consumed is still present in your body — keeping you alert. And, if it’s bedtime, potentially keeping you from falling or staying asleep.