I'm a kind of person who have to drink a large cup of coffee in every morning and a big can of energy drink in every evening. So, stop this behaviour is not easy for me as I feel like I have become addicted to them.
I clearly know that consuming too much caffeine (more than 2 cups per day) can cause my future health problems as well as affect my good night sleep (It just affected my night again last night as I woke up a few times during the night, thanks to "Starbucks' Venti Mocha").