Very few drugs have experienced waves of bearish and bullish controversy quite like caffeine, except perhaps MDMA and Kratom. Arguably, it’s one of the most important substances in the formation in our society, as food and drug journalist Michael Pollan outlined in his short book, Caffeine: How Coffee and Tea Create The Modern World.
Caffeine is so damn powerful, it’s hard to imagine, for both better and worse, our 9-5 industrial society without it. Employers not only provide it for workers, but they give paid time during the workday to consume it.
So there might be something to this whole caffeine thing. Like almost anything else in life, it’s not categorically good or bad. It has benefits and drawbacks. In certain situations, it can give you the extra push to perform, whether in the gym or at your gym. At other times, it can have disastrous downstream effects.
I say perceived energy because if I just say energy, somebody is going to comment and say “well technically it doesn’t improve energy because it has no calories.” So let’s be more clear here on what happens on a physiological level. First, caffeine wards off sleep by blocking the adenosine receptors in your brain. So if you’re sleep-deprived, it can help you stay awake, giving a perception of more “energy.”
It also clearly correlates to an increase in sympathetic hormones like epinephrine (adrenaline, if you’re British) and cortisol. As we talked about in this article how to fall sleep fast, sympathetic hormones and parasympathetic hormones regulate what we call our circadian rhythm, or internal clock. Daytime activities like exercise and sunlight increase sympathetic nervous system activity, while darkness and relaxation increase parasympathetic nervous system.
Caffeine increases these sympathetic hormones, allowing us to stay alert and focused easier. It can even increase dopamine, giving us jolts of feeling good (which partially explains why it’s so addicting.)
Like most drugs, you lose sensitivity with consistent use. If you drink coffee every day, it’s part of your normal experience. Not drinking coffee leads to caffeine withdrawal, which begins to touch on some of the potential problems with caffeine.
Whether caffeine as an isolated variable improves performance isn’t as clear as companies trying to sell you stimulant-stuffed pre-workout supplements would like you to believe. As we’ll touch on in a bit, the jury is still out on whether or not caffeine improves performance indicators like mental capacity, as measured by something like chess performance, let alone physical attributes like speed and power.
What we do know, though, is that if you’re in a sleep-deprived state, you start to suck at everything. Caffeine and the alertness it brings can mitigate the short-term effects of sleep deprivation. On days where you were up late or had to get up early, caffeine can be a great tool.
This will be the most controversial statement about this article. The problem with studying people on caffeine vs not on caffeine is that so much of the population is dependent on caffeine, then when you compare two groups, the group not currently taking caffeine is actually in caffeine withdrawal.
Of course, if you take two otherwise equal people who always drink coffee, and you make one group suffer without it, the one with coffee would crush them at everything. This doesn’t actually prove much about caffeine’s benefits in a vacuum.
To properly study this, the control, non-caffeine group would have needed to not use caffeine for weeks to reset their sensitivity to it. In terms of bringing people in for a study then, it becomes a challenge. What’s more, many studies on caffeine haven’t considered whether the performance differences take caffeine withdrawal into consideration.
This has the popular thought that caffeine in nearly all cases increases performance, when that’s still unclear at this point.
The ugly side of caffeine is that we already live in a culture tasked with existing too much in a sympathetic state. (Pollan would argue caffeine has something to do with this, so we end up with a chicken-egg discussion.)
Nonetheless, drinking caffeine throughout the day, and definitely at night, crushes our sleep. I’ll save why sleep is so important for another time, but if you want to die young and feel like shit, then sabotage your sleep as much as you can.
Many regular coffee drinkers will anecdotally report that caffeine, even in the evening, doesn’t impact their sleep. However, when looking at their sleep data, it’s clear that they were “passed out” in light sleep more than their non-caffeine-induced counterpoints.
They had less REM and deep sleep, and the next day felt more drowsy. This then would prompt people to, that’s right, have more caffeine. We can see how this would become a vicious positive feedback loop very quickly. This is true even in groups that halted caffeine use a full six hours before bed.
Our caffeine curfew then, should be even earlier. While it depends on the person, a general, safe rule of thumb is to finish caffeine intake by noon.
Pollan mentioned in his book that one of the most interesting aspects of his research was that every single sleep expert he interviewed had sworn off chronic caffeine usage. This alone should cause second-guessing whether you want to be taking it every day.
Now, of course, it gets complex. Lots of research has independent health benefits on regular coffee usage, for example. One strategy that coils all of this together into a balanced approach is to use caffeine only when you need it. Instead of taking it before every workout, take your pre-workout on your hardest or least favorite day for an extra boost. (For athletes, only take it on game day, that way you maximize its effects.)
Having it a few days a week, on your most challenging workdays, or on Sunday mornings because you always go out on Saturday, allows you to get the performance and attention boosts, without regularly sacrificing your sleep and nurturing caffeine dependence.
Caffeine withdrawal is a whole other mess, which we’ll touch on in a later article.
Caffeine in many ways epitomizes one of the challenges of the human condition: nothing’s ever as black and white as we may like it to be. We can’t call it ‘healthy’ or ‘unhealthy’ and move on. Next time you get frustrated because an expert responds to a question with “it depends” remember that the truth almost always lives in the nebulous gray area, where each circumstance is a little bit different. That’s the situation with caffeine.
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