But for years, coffee had a bad reputation. Linked in many people's minds with smoking, coffee is associated with over-caffeination and insomnia.
The caffeine found in coffee can stay in your system for up to 12 hours, making it more difficult to fall asleep, and it affects your quality of sleep as well. Caffeine is also a diuretic, meaning that it increases urine output, which can lead to dehydration.



