Did you sleep less hours last night? Then most probably you drink coffee throughout the day to stay sharp and awake. Are you a shiftworker? You take coffee for the same reasons. And there is nothing wrong with that, if coffee is taken in moderation (up to 4 cups a day) and doesn’t influence your sleep quality.
According to a recent report of the Institute for Scientific Information on Coffee (ISIC), the effect of coffee can last for several hours, depending on how quickly or slowly it is metabolized by your body. It also depends on the amount consumed throughout the day, individual sensitivity, and consumption habits.
If you notice that drinking coffee later in the day disrupts your sleep quality, then better limit your coffee consumption up to 6 hours before bedtime and switch to low caffeine drinks, or decaffeinated coffee during the afternoon and evening.
Curious? HERE is the source