My 16-month theanine self-experiment

”I’ve long found that tea makes me much less nervous than coffee, even with equal caffeine.”

Well, of course you are less nervous when you avoid taking coffee: it contains a LOT of beta-carbolines which act as MAO-A inhibitors. MAO-A inhibition directly prevents adrenalines from being inactivated by oxidation.

How do you define "a LOT"? the only estimate I can find says there's 210mcg/L of beta-carbolines. Mainly harman and norharman, which have a binding affinity for MAO-A of 220nM and 2200nM respectively(lower is more potent). Not earth-shatteringly potent. These compounds have a fairly short half-life and they're reversible.

Doesn't seem to be anywhere close to the potency of MAO inhibition used in psychiatric or entheogenic contexts. I'd be reluctant to attribute too many noticable effects to them.