Midterm season is upon us all too soon; hopeful promises to ‘lock in’ loom large, and caffeine consumption reaches new heights, whether in the form of a tea, coffee, energy drink — or all three. Caffeine seems to transform from a fun little drink into a necessary ingredient in study routines. But, although we know that caffeine does in fact do something, the ways in which it works — and works less well the more you drink — can seem like a mystery. So, what’s the science behind the sip?
To understand the effects of disturbing a system, let’s first take a look at what normally happens in the brain. Adenosine — an organic compound similar to the nucleic acids present in DNA but missing certain phosphate groups — has been shown to be a key component in the regulation of sleep. It is important to note that sleep regulation is a complex system that involves many more pathways and molecules than just adenosine. However, one of caffeine’s primary mechanisms of action is heavily tied to adenosine, and thus that is the focus of this article.
As you stay up longer, adenosine triphosphate — which you may recognize as the energy-rich molecule that helps power many biological processes within your body — accumulates. The body responds by degrading adenosine triphosphate into adenosine, leading to the increase in concentration of adenosine. More adenosine molecules will thus bind to more adenosine receptors, and this stimulation has different exact mechanisms of action in varying brain regions. The overall effect, however, is that sleep is promoted by inhibiting wakefulness.
Caffeine has a very similar structure to adenosine and thus is able to ‘fit’ in the adenosine receptors. Since caffeine will take up the space of an adenosine without stimulating the receptor, it prevents actual adenosine molecules from binding to their appropriate receptors and eventually has the effect of not promoting sleep — leading to the wakefulness that many crave caffeine for.
Continued caffeine consumption, however, eventually results in the production of more adenosine receptors in order to balance out the constant blocking of the ones you already have by caffeine. Because of this, it will now take more caffeine to similarly suppress your adenosine receptors — it will now take more caffeine to feel the same wakefulness.
College can feel like a time when you’re always behind — always needing to write one more paper, study for one more test, go to one more event, add one more thing to your resume. Sometimes, it can feel like caffeine is the only way to keep up. The thing about caffeine is that it works well, until you suddenly need two energy drinks to feel as awake as you did with a single coffee a couple months ago.
This is by no means a call to stop drinking caffeine — I, myself, am sipping a double-shot latte while writing this. But, maybe substitute your next Dunkin’ stop with a power nap, or pump up your adrenaline with a short workout instead of getting another energy drink. Take some time to recharge and reset your brain — before the caffeine slump causes your next crash out.
