I realized the other day that I don't really understand why coffee does what it does for me though. Yes, I recognize what it does for my soul -- my affection for it, it is my teddy bear or security blanket. But what is it doing to my body when I drink it?
I've always assumed that caffeine got in my blood stream somehow and made my heart pump faster which then made other stuff go faster...never really thought too much about it though.
So, for those of you who are like me and might have learned about it in Bio 101 class and forgot completely about it...or for those who think it's just magic...here's the rundown as I have learned it.
To understand how coffee get's you going, ironically, you must first understand how the brain sleeps.
We have receptors in our brain that receive certain types of molecules. The ones we are concerned about are receptive only to xanthine family molecules. Our brains also produce something called adrenosine which is in the xanthine family...they like to sleep together. That is, if a receptor receives adrenosine, it tends to make you drowsy and this is how you get your sleep. Picture a nice child who has a baby sitter over and they read books and fall asleep so easily because they've been doing it since the child can remember.
Enter caffeine, a cousin to adrenosine...they are both in the xanthine family and the receptors latch onto these caffeine molecules very naturally and in effect, this actually blocks the adrenosine from attaching.
This alone is enough to keep the synapses firing faster than normal since the adrenosine slows it all down.
However, this blockage also triggers an alarm that wakes up the Pituitary gland -- Pituitary didn't know the cousin was coming over to play and sends a quick message to the Adrenal gland that something's not right...the brain's not getting the Adrenosine it normally gets. The Adrenal gland then sends out a does of adrenaline which in turn triggers some other repsonses:
"liver releases sugar into the blood for extra energy, pupils dilate, heart beat increases, breathing tube opens more, etc. Caffeine is also said to increase dopamine levels much like amphetamines do, which produces a euphoric effect. It potentially does this by slowing the rate of dopamine re-uptake." (taken from: http://www.psych.umn.edu/courses/spring05/dionisiod/psy3061/caffeine.htm )
So there you have it. That's what caffeine does to us...well, does to our physical bodies. So next time you p'shaw someone calling you a drug addict because you love coffee...embrace it. We are all drug addicts by nature, and that's okay because you know how it works.
The squeaky wheel gets the oil.
The obnoxious child gets the baby sitter fired up.
The parent gets the coffee.