So how does coffee works?
Caffeine, the active compund found not only in coffee, but also in tea and chocolates, competitively inhibits adenosine, stimulates epinephrine production and delays dopamine degradation. Yey!
When is the best time to drink coffee?
Studies have showed that the levels of cortisol is directly related to one's level of alertness. Hence, if your cortisol levels are high, you don't really need that extra buzz you get from coffee.
Cortisol levels peak around eight in the morning, then rises again around lunch time and again, around six in the evening. Hence, ideally, you don't have to drink coffee around this time because these are the times that you are most alert. Rather, drink coffee just before your cortisol levels dips just around 0930H, or around 1500H. It is not advisable to drink coffee in the evening, especially if you have no reason to sleep late. Tada!