You're Probably Drawn To Coffee More Than Beer & Here’s Why

You’re reading this with a cup of coffee in your hand, aren’t you? That’s okay; I’m writing it with a mug next to my keyboard. And we’re in good company. Globally, almost two billion cups of coffee are downed daily. Canadians drink more coffee than beer by a ratio of almost three to one.

Why such a buzz about coffee? Well, the buzz, actually. Coffee and tea are the two most consumed beverages in the world. Both are caffeinated and that’s no coincidence. While coffee is a tasty brew, most people drink it, at least in part, for the caffeine jumpstart.

Caffeine is naturally present in coffee, tea, and cacao (the plant whose seeds give us chocolate) trees where it dissuades caterpillars from leaf-munching — or possibly wakes up their pollinators (seriously). What is important here, though, is that caffeine is a dead ringer for adenosine, a chemical messenger called a neurotransmitter. In us, and most other animals, adenosine naturally binds to receptors in our brain and triggers a cascade of molecular events that help us to sleep and rest.

The caffeine in coffee wakes us up by binding to adenosine receptors in the brain and blocking this natural cycle. Caffeine’s structure is similar to that of adenosine, but not identical. Similar enough to bind to those specific receptors, but different enough to keep them from working correctly. In binding, caffeine displaces adenosine from its receptors, blocking the natural rest cycle — and waking us up.

This blocking is also the reason why too much coffee can leave you feeling jittery or sleepless. You can only postpone fatigue for so long before the body’s regulatory systems begin to fail, leading to simple things like the jitters, but also potentially serious complications like anxiety or insomnia. You’re not imagining it — coffee really can keep you from sleeping well. In fact, a possible link between coffee drinking and insomnia was identified over 100 years ago. The key to waking up in the morning and still sleeping well in the evening is likely moderation.

On the plus side, the binding also triggers the release of a series of chemical messengers and neurotransmitters, including dopamine — the feel-good neurotransmitter that is part of the buzz associated with exercise and sex — and cocaine. That’s a pretty powerful morning pick-me-up.