How to Make 4.1 Billion People Mad

One of the most valuable lessons you can learn about writing high-performing copy is not to try to make people believe something brand new.

There’s not enough time on the page. Beliefs are a function of identity and they’re tied pretty tightly to existing values and experiences. It takes a while to untangle them.

So copywriters don’t play that game. Instead, we frame products or services for customers in a way that not buying feels at odds with who they already are.

But this isn’t a sales page so I have the freedom to say something sacrilegious.

Caffeine is slowly killing you.

Perhaps not you. But a good portion of the population. More than half. Because while 9 out of 10 people drink caffeine every day, 5 out of 10 shouldn’t.

Across the world, that’s 4.1 billion people who need to read this memo.

As it is, they’re paying a significant biological penalty and imbibing a ticking time bomb of health risks.

To get precise, there’s a 55% chance I’m talking about you. In this memo, I’m going to explain why I’m saying this and I’m going to tell you exactly what to do about it.

Then, at the end, you find out that you’re in that statistical bucket, you can consider yourself lucky you landed on this page today.

Uncommon Grounds

Around 850 AD in Ethiopia, a boy noticed his goats bouncing around in the sun after munching on some bright red berries from a wild shrub.

He shared his discovery with the local monks, who started using the Coffea arabica plant to add vigor to their prayer and meditation.

A thousand years later, having powered both European Enlightenment and the Industrial Revolution, caffeine rituals persist.

From the home brew to the drive-thru, they help us to shape our days and give us a sensory and behavioral cue to lock in, focus and get shit done.

And let’s not forget the micro glamor of a cup of coffee. From Breakfast at Tiffany’s to James Bond, each cup pays homage to a powerful and intoxicating brew of psychological, sensory and social factors.

So what’s not to like about caffeine, its role in our days and rhythms, its place in our homes and offices, its importance in dragging civilization out of the dark ages?

Well, here’s a pair of curious divergent cultural metaphors that illustrate mankind’s complex relationship with the mighty molecule.

Alexander von Humboldt, the great German naturalist, called coffee “concentrated sunshine.” But the Native American Indians – who also knew a thing or two about Mother Nature – had a very different name for it: “empty fire.”

It lights you up, that’s for sure. It accelerates your metabolism and excites the nervous system, but relevant to the extra work it causes provides almost no nutritional value to compensate for the stimulatory response.

What’s burning beneath the surface? The rituals and folklore represent deep shifts in mood and energy, but it’s the chemistry inside our bodies that determines whether those sparks are good for you or not.

A cup of caffeine is an encounter with a potent molecule whose effects extend far beyond energy or alertness. To understand both its promise and its peril, we must dive into the science of what happens once we swallow.

The Pharmacodynamics of Caffeine

The reason 1,3,7-trimethylxanthine (caffeine’s chemical name) has grown to dominate the globe is to do with its promise of productivity.

We have come to know that it fuels our attention, our work, our routine. But the “lift” you feel in the morning is an illusion.

If you drink caffeine every day, that first jolt from the morning cup of joe is not so much the hit of caffeine but the suppression of withdrawal symptoms.

The pharmacodynamics of caffeine match our body’s rhythm so neatly that the morning cup syncs with the first signs of need-a-fix symptoms.

Every day, caffeine ironically but relentlessly presents itself to us as the quick and tasty tonic for the mess it made in our minds and bodies the day before.

It makes us faster, but not smarter. Productive but not necessarily creative. More energized but a little less empathetic.

There’s a book called The Diagnostic of Mental Disorders and since 2013 caffeine withdrawal has been listed in there as an official psychiatric diagnosis.

This explains why you often see coffee queues. You’re witnessing an orderly line of addicts who are just patient enough to stand in line to get their fix and return to baseline.

So while caffeine’s a seductive pleasure and a productivity cue, for 55% of the population it’s also a silent and insidious handicap, quietly gnawing away at their wellbeing.

Children and adults of all cultures are drinking caffeine every day. But the answer to whether or not you specifically should drink it is written in your DNA.

The Genetic Ghost in the Machine

There are three variations of the gene CYP1A2, which determines the speed at which your body processes caffeine.

If, like 45% of humans, you have the AA variant, that means you’re a fast metabolizer and it’s safe to drink caffeine nine hours before sleep time.

If you have one of the other two variants, AC or CC, then you shouldn’t drink caffeine at all.

Here’s the breakdown:

Slow metabolizers are more likely to suffer from anxiety, sleep problems and high blood pressure as first order effects.

But downstream of this is the more insidious reality of long-term sleep impairment. We’re talking higher cardiovascular and metabolic risks, mood disorders, accumulation of Alzheimers-causing proteins and smaller testicles.¹

Medium metabolizers may not get an anxiety spike from an Americano, but the hidden health tax is the slow but relentless battering the architecture of their sleep is taking every day.

So what this amounts to is Russian Roulette with biology on a massive scale. Caffeine has become a universal habit, but one with unequal risk.

It’s a paradigm shift to understand the significance of this.

When Michael Pollan was putting together the caffeine chapter of his book This is Your Mind on Plants, he interviewed the influential American psychopharmacologist Roland Griffiths.

He asked him whether he thought caffeine was a boon or a bane to our civilization:

“Given the way our culture works, that we have times we need to be awake and asleep and need to report to work at certain times. We’re no longer able to just respond to our natural biological rhythms, so to the extent that caffeine helps us sync up our rhythms to the requirements of civilization, caffeine is useful. Whether that’s helpful to our species is another question.”

There’s a hidden health tax to caffeine that isn’t getting enough acknowledgement.

It’s never occurred to anyone to check their DNA before they fine grind their morning brew.

How Caffeine Hijacks Sleep

Wellbeing articles tell you that to get a good night’s sleep, cut back on cappuccinos, try a hot bath, pop some magnesium pills and follow a wind down routine before bed.

All of the above have merit, but what they don’t tell you is that at a physiological level, elite sleep is about balancing three hormones; adenosine, cortisol, and melatonin.

Adenosine is a naturally produced hormone in the body. It is responsible for how sleepy you feel. It starts building sleep pressure in the body when you wake up.

When adenosine levels in your body peak, you will have a strong urge to sleep, usually 12–16 hours after you get out of bed.

Unless, that is, you drink caffeine, which blocks the natural adenosine sleep signals to your brain. The need for sleep remains, but your body doesn’t know it.

Caffeine also raises cortisol levels in the body. Cortisol is a stress hormone, and elevated stress equals compromised sleep.

Melatonin (known as the vampire hormone because it comes out at night) is another naturally occurring hormone in the body, not just a pill they sell at the pharmacy.

The quality of your body’s melatonin production depends on the amount of natural daylight you get during the day and is suppressed by the amount of artificial light you get at night.

This trifecta of hormones is the lens through which we should interpret all the other variables that might affect the quality of our sleep.

To summarise the conditions that are inherent in the existence of these hormones, to get high-quality sleep, your body needs to:

• Feel sleepy (adenosine receptors are clear)
• Be sufficiently relaxed (cortisol is not elevated)
• Know what time it is (melatonin production is not corrupted)

The Unseen Architecture of a Double Shot

Lots of people claim to be able to sink a double espresso after dinner and sleep like a teenager. But what they’re missing is that the quality and architecture of that sleep has been banjoed.

Even after falling asleep, caffeine reduces deep slow-wave sleep (SWS)—the stage critical for restorative physical and cognitive recovery—by 20-30% and chops up REM sleep, which keeps your emotions and memory in check.

Caffeine has a surprisingly long half-life. On average it takes 6–7 hours for half the caffeine to leave your body. This means that it actually has a quarter-life of 12–14 hours.

If you have a cup of coffee at midday, then a quarter of that adenosine-blocking syrup is still swilling around in your brain at midnight. That’s right: a lunchtime coffee is the same as drinking a quarter cup as the clock strikes midnight.

And the problem is that even for fast metabolizers, caffeine can stick around in the system for 15-35 hours. If you go cold turkey, withdrawal symptoms can last up to 9 days.

Most of us have lived our whole adult lives occasionally mumbling about feeling groggy or moody or forgetful, but without ever having known what it feels like to be caffeine free.

The truth is that for medium or slow metabolizers, even one cup before midday can visibly harm restorative sleep.

Caffeine users fall asleep 2.5 times slower, sleep for 1 hour less, and experience approximately 11.43% lower sleep efficiency compared to their caffeine-free counterparts.

These deficiencies compound day after day, week after week, year after year.

This crumbling architecture shapes our sleep, our mornings, and our memories.

It is trampling on the human experience.

The Civilisation–Species Paradox: Progress at a Price

There’s been an undeniable collective gain to the accidental discovery of caffeine. But our genetic differences mean that some people are taking an unnecessary hit, harming themselves in the pursuit of conformity and efficiency.

Caffeine’s global appeal ignores the 55% of people whose CYP1A2 genes make them medium or slow metabolizers, turning a morning ritual into a health liability.

There’s a parallel here with workout culture. A 2025 review in online science journal Frontiers in Physiology, pulled from 43 trials with over 2,000 participants, concluded that nearly 50% of all gym time is wasted because people are not exercising according to their body type.

In other words, they are falling in line behind an idea or a vision instead of choosing what would otherwise work better for them.

In both cases, we chase societal ideals—ripped abs, better focus or just the sense of belonging that comes with sharing a flat white with a friend—while neglecting the genetic blueprints that should guide our choices.

That mismatch between biology and expectation is the true paradox: the human race advances by amplifying overall productivity, yet individuals pay the cost when their bodies aren’t built for the template.

Reading Pollan’s book, he concluded that overall caffeine has been a boon for civilization. And I agree, there’s a clear net benefit.

But I’ll add two caveats.

Firstly, there is no mention of the CYP1A2 gene in Michael Pollan’s book. In an otherwise compelling and well-researched read, this is a strange omission.

Secondly, if you were to take a genetic test and find out that you are a medium or slow metabolizer, would you continue to drink the stuff?

At a basic level, this is a question about ritual versus biology. Caffeine – culture’s glue – up against the reality of our individual genetic wiring.

True progress might mean redefining efficiency, not as conformity to a universal standard, but as the courage to tailor our habits to our DNA.

How to Redesign Your Relationship With Caffeine

If you’ve made it this far, you’re probably wondering: okay, smartass, what now? Toss my French press in the trash and go for an almighty sulk?

You could, but as someone who’s done the whole cold-turkey thing, I can’t recommend it. The headaches on Day 3 are unpleasant.

First, find out your CYP1A2 gene. Get tested. Services like 23andMe or AncestryDNA can deliver your variant in a couple of weeks for under $100.

If you’re AA (fast metabolizer), congrats—you’re in the elite minority. But if you’re AC (medium) or CC (slow), it’s time to rethink the habit.

If you can’t or don’t want to get tested, the smart move is to play the odds. There’s a 55% chance you’re in the “nope” bucket. Better to err on the side of caution.

Start by cutting your intake by 25% every few days. If you’re on three cups a day drop to two, then one-and-a-half, easing into decaf hybrids if needed.

As you taper, monitor your sleep. Grab a wearable like an Oura Ring or Whoop strap. Track your deep sleep stages, heart rate variability, and how long it takes to nod off.

You’ll notice the architecture shifting: more slow-wave sleep for that bone-deep restoration, and fewer REM interruptions which will give you a boost in memory, emotional regulation and creativity.

Timing is everything, especially if you’re a fast metabolizer clinging to your vice. A workable rule of thumb is no caffeine after noon. Use apps like Caffeine Tracker or Zero to log doses and predict clearance based on your variant. For the rest of us, aim for zero.

But track the wins: journal your energy levels, mood swings, and focus. You’ll uncover patterns. You’ll come to understand that the grogginess was caffeine dependancy, not your natural state.

Replace the Ritual

Caffeine is used as a cue for productivity, a social lubricant, and moments of mindfulness. So removing it can be jarring if you don’t swap in alternatives.

There’s journaling, prayer, affirmations, meditation or breathwork. These are ancient human practices that let your brain wander and reset without the chemical stranglehold. Or just go outside and touch grass. Each to their own.

The point is humans are wired for bursts of creativity and adaptability, not endless grind. When you ditch caffeine, you reclaim that balance through deeper rest that breeds sharper ideas, better moods, and resilience.

Don’t look at it as slowing down or giving up. It’s a step forward. You’re syncing up with your own blueprint, trading empty fire for inner sunshine.

In the end, this isn’t so much a diatribe against caffeine as it is a plea for a truce with your DNA. Test, taper, and track. Your brain (and those 4.1 billion others) will come to thank you.

For now, I will leave you with the words that were inscribed in the Temple of Apollo in Delphi at the foundation of western culture. They surely bear repeating here, at civilization’s stress-frazzled apex:

“Know Thyself”