Why Should You Have A Cup of Coffee, Everyday?

People always ask me: "How can you drink coffee everyday? Why do you even do that?" and I can't but say:"She the best friend you could ever have. Whenever you try it you become unable to live without it...." and I always see the same reaction: Laughing.
But a cup of coffee was viewed as an essential part of our everyday life, and here are some reasons why one should have at least a cup of coffee everyday:
Drinking black coffee keeps you  healthy, where according to studies, people who drink four or more cups of coffee have a lower rate of developing liver cancer.
Coffee also keeps you calm where its smell gives you a feeling of relaxation, so if you are stressed because of not getting enough sleep, coffee would make you calm and satisfied.
Coffee simply boosts your mood.