Caffeine helps keep your body alert and boost brain function throughout the day.  It is the stimulant in both coffee and tea, but it is more prevalent in coffee compared to tea.  However, caffeine amount in tea can be easily matched to the amount in coffee by increasing tea mass.  On the other hand, increasing coffee dose or frequent coffee consumption can cause an upset stomach and acid reflux due to coffee being an acidic beverage (ph 4-5).  Green tea is alkaline (ph 9), making it a great counter-substitute for off-days on coffee.  Other than coffee being acidic, coffee is the still best source for daily caffeine consumption.  But green tea has something coffee doesn’t.

One of the main reasons why green tea is a more effective nootropic is that it naturally contains amino acid L-theanine which is a compound that is able to cross the blood-brain barrier.  When crossing the blood-brain barrier, L-theanine increases GABA, a neurotransmitter responsible for anti-anxiety.  Alpha wave and dopamine production is also increased.  For coffee, L-theanine needs to be supplemented separately.  L-theanine has a calming effect opposite to caffeine creating a synergy between the two active ingredients.