Caffeine is everywhere. It’s offered for free at office jobs across the U.S., in waiting rooms at the dentist or the mechanic, and it’s even in chocolate. It’s so prevalent that it can be hard to remember that caffeine is a drug.
Consuming caffeine on a regular basis can create a dependency, where you rely on that caffeine to provide reliable energy. You can also build up a tolerance, and need to consume more caffeine over time to feel the same effects.
Recently, I learned how caffeine is processed in the body. A common misconception (one that I believed for years) is that if you drink a mug of coffee, that caffeine will be out of your system “in six hours”. That’s the number I’ve heard thrown around most, six hours.
In reality, that’s not how the body processes caffeine. Instead of working through caffeine in a constant time (after six hours) or a linear time (X milligrams of caffeine processed every hour), it processes caffeine and many other drugs in terms of the drug’s half life.
This means that when the “half life” has elapsed, half of the drug has been processed and half is still in the body. As another half-life elapses, half of the remaining amount of the drug is processed, and so on, until the last little bit is gone.
This creates a curve. Caffeine is used up quickly at first, forming a steeper drop, and then it slows down as there is less caffeine in the body, forming a line that is less steep.
An average 8oz cup of coffee has around 100mg of caffeine. The exact amount can vary based on the beans, the brewing method, and the coffee-to-water ratio, but this is a good estimate. The half life of caffeine is between 4 and 6 hours for most people. Again, this can vary based on the person’s biology and intake of other drugs, but this is the average.
This means that a person who drinks a cup of coffee at 8am still has 50mg of caffeine in their system by 1pm. By 6pm, there’s 25mg. By 11pm, there’s still 12mg. It’s unclear how much caffeine can have a negative impact on sleep, but based on general recommendations by the FDA, I would estimate that between 30mg and 50mg is enough to be disruptive.
That’s for one cup of coffee, consumed first thing in the morning. If you were to have a second cup of coffee a couple hours later, say at 10am, you create another spike and restart that curve. By 10am that 100mg of caffeine will have reduced to about 75mg. Add another 100mg on top of that and now you have to go through another three half-lives (fifteen hours) to get below 30mg and another three after that to get close to zero.
Understanding this curve helped me realize just how much an afternoon coffee can disrupt sleep at night.
What does this mean for coffee-lovers like me?
A few weeks ago, I was at the point where I was drinking an average of 250mg to 350mg of coffee every day. This isn’t the worst thing I could be doing, and it is within the FDA’s recommended limit of 400mg per day. Caffeine is fairly harmless and I don’t want this to scare anyone.
Still, I could tell that I was using it as a crutch to wake up in the morning, drinking it far too late in the afternoon, and disrupting my sleep. It’s a vicious cycle, because I’d have trouble sleeping, wake up tired from lack of sleep, then and drink more coffee to help myself wake up.
I don’t like the idea of being dependent on anything. It’s like owing a debt. I didn’t want to need a cup of coffee to start my day, or pay the consequence of fatigue and headaches.
So I quit.
How I Quit Caffeine
If you use caffeine as a daily ritual (enjoying a coffee or a soda at a particular time of day), I would recommend simply replacing it with a similar beverage that doesn’t have caffeine in it. Often, the habit of fulfilling that part of your routine can be the most powerful obstacle. So don’t break the habit, just change it a little bit.
I drank some delicious hot cinnamon tea, ginger ale, and a chamomile tea in the evenings. You can also try decaf coffee! I haven’t tried decaf whole beans myself, but I know they exist and people enjoy them (Wheezy Waiter on YouTube recently replaced his coffee with decaf).
There are ways to wean yourself off of caffeine slowly, but I’m a cold-turkey kind of person. I like to rip the bandage off and get it done with. I quit caffeine for a month a few years ago, so I had some expectations for what the withdrawal process would be like, and how long it would take. During that month, the only major caffeine withdrawal symptoms I had were headaches that lasted for 8 straight days. Afterward, I felt totally fine.
This time was different. The withdrawals were a lot worse, likely because I was drinking a lot more caffeine this time around, every day for a few years. I have a vlog-style video of my experience quitting caffeine this time, but keep reading and I’ll summarize my caffeine withdrawal timeline here, too.
Day 1: Headache
On Day 1 I was dead tired. By the afternoon, when my body realized it wasn’t getting its favorite treat, I developed a bad headache. That night, I was so tired I didn’t even feel like checking in with the vlog. I sat in my desk chair, feeling useless, and looked blankly at the internet until I went to bed at 9:30pm, completely exhausted. This was a really early bedtime for me. I typically get in bed around 10:30 or 11 and fall asleep around midnight.
Days 2 - 5: Body Aches
My headache continued and I developed a fun new symptom: my body ached. The body aches got worse during days 3 through 5 before they finally let up.
This was the worst caffeine withdrawal symptom because it was constant. Moving or standing made the pain a little worse, but sitting or laying down didn’t make it better.
It was so bad that I considered that I might have gotten sick at the same time (though, this is highly unlikely because I rarely leave the house). Taking ibuprofen helped with the body pain, but it was persistent and would return full-force a couple hours later when the ibuprofen wore off.
Days 6 - 13: More Headaches
Once the body aches cleared up, I had a few more days of headaches, but these may not have been caused by the caffeine withdrawal. I do get headaches often anyway, so it’s hard to say whether it was connected.
I did feel like the caffeine-related headaches were accompanied by severe eye strain. I spend most of my day staring at a computer, so this is another symptom that could be unrelated to the caffeine, but it felt much worse than usual for me. In the early days of caffeine withdrawal, I felt the eye strain hit first thing in the morning rather than after hours of computer use.
On these days, my headaches got slightly less intense each day. After two full weeks, I was feeling like myself again. Time to dive back in.
Reintroducing caffeine
After my little detox, I did start drinking caffeine again. This time, I’m being careful to use it mindfully, making sure that my body gets a rest from time to time. I’m aiming for at most one “serving” of caffeine per day, in the morning. A single cup of coffee, or a mountain dew, not both.
Like I mentioned, caffeine is not a dangerous drug for most people. You don’t need to quit it cold turkey (unless you want to), and there are probably things you're doing that are a lot worse for your health (like sitting).
I just want to make sure I’m giving myself the best chance to feel good in my body. Sleep affects everything we do, and it’s hard enough to get sleep without chaining together days of chemical stimulants.
I’m going to continue enjoying a cup of coffee some mornings, just not every morning.