Co-written with Gene Food staff.
Caffeine gives me the jitters, which makes sense in light of my genetics. I am homozygous for the CYP1A2 gene, which means I metabolize caffeine more slowly than some of my buddies who drink espresso rather than warm milk before heading off to bed.
When I was first reviewing my genetic charts, this information made perfect sense to me as I’ve always felt caffeine affected me to a greater extent than many of my friends. If I were to drink a latte before bed, I’d be up half the night tossing and turning, so I usually choose green tea over coffee.
However, despite knowing that large doses of caffeine don’t work well for me, I will occasionally still go on a run of morning espressos for a few days straight. When I come to my senses and quit the coffee, inevitably a withdrawal period begins, usually with a headache for a couple days and a feeling of sluggishness.
Caffeine may be the world’s most popular drug, but it’s still a drug and experiencing withdrawal is a great reminder of this fact.
Progression of caffeine addiction
The first time in recent memory I went on a sustained coffee blitz, I was hanging out in sleepy San Diego, which if you haven’t been, is a city characterized by the country’s best weather, and a corresponding dearth of work vibes.
Caffeine seemed in some strange way necessary to prevent joining with the collective slumber. I was on Austin time, so I’d wake up at 5:30 every morning and walk my dog, Ned.
On these walks, we’d stroll past an open air coffee concept called Lofty Coffee, in San Diego’s Little Italy neighborhood. Here’s this completely outdoor coffee shop, with great branding and a fine selection of different caffeinated drinks to warm you as the marine layer rolled out. The people “inside” looked so happy and content sipping on their various black water beverages. I couldn’t resist. It was time for me to join the ranks of the coffee tribe.
Caffeine addiction and developing a tolerance
For about 10 days in a row, I ordered a Turkish Latte, which is offered at Lofty with house made coconut milk, and cardamom. On day one, I had a rush of euphoria that lasted an entire day. I felt like I could take on the world. My brain went into high gear. Mood was improved, productivity was up, smiles were in plentiful supply. Optimism flowed. And that ride lasted through about day four. But on day five, I noticed that the buzz wasn’t quite as good as it had been on previous days. When I finished my latte, I immediately wanted another, but to keep things in check, I would order a decaf Americano as a follow up. Later in the day I would have multiple cups of green tea.
In other words, the returns diminished as I drank more caffeine.
I was developing a tolerance.
By day 6 or 7, a latte on an empty stomach gave me a little bit of what could best be described as sour stomach. By day 9, I seriously considered ordering a double, but never did.
You get the point.
Caffeine withdrawal – breaking the addiction
A couple mornings during my run I’d wake up, and think, “you know what, I will skip the coffee this morning, I don’t need it.” But inevitably, I’d show up at the coffee shop for my latte nonetheless, rationalizing the trip the whole way.
Hey, coffee does lengthen telomeres, right?
Then, one day I stopped cold turkey. No latte, no decaf Americano, no multiple cups of green tea in the afternoon. What happened next came as a surprise.
I developed full on caffeine withdrawal. I felt like an addict drying out at a rehab center.
My caffeine withdrawal symptoms
The day I opted out was a day marked by these symptoms:
- a terrible headache,
- stomach upset,
- and some lightheadedness.
- I was irritable and cranky.
- I legitimately felt like I was sick, except I knew I wasn’t.
I stayed in bed a good chunk of the day and got very little done.
As I clicked off more caffeine free days on the calendar, I returned to normal, but the experience of having a true withdrawal from an actual drug was a first for me and it was eye opening. It got me wondering, did my CYP1A2 genotype have something to do with the severity of my withdrawal?
I’d read that coffee constricts blood vessels in the brain, and that when you quit, the passageways open back up, which causes a headache. But I wanted to real scoop on what causes withdrawal, so I asked, you guessed it, Aaron, the badass scientist on our team. Here’s what he had to say.
The science of caffeine withdrawal
Thanks John. There’s actually a really nice study which looks at just this effect. Published by researchers from the University of Vermont and Johns Hopkins University School of Medicine, which you can read here if you’re interested in understanding everything. While the study was small, only 16 subjects, it was double-blinded (neither the subjects nor the researchers know which treatment a person is on) which is the gold standard.
The regular caffeine users switched between a maintenance dose of 400 mg of caffeine or a placebo without any caffeine, and at regular points received either high dose caffeine or placebo challenges. The idea behind this switching is to see what effects a chronic and acute withdrawal from caffeine would have on people with differing daily intakes.
To give you an idea of the dosing see this table from Amber’s previous post.
|Beverage type||Caffeine per cup (8 oz)|
|Coffee (brewed)||95-165 mg|
|Energy drink||27-164 mg|
|Black tea (brewed)||25-48 mg|
|Green tea (brewed)||25-29 mg|
|Decaf coffee (brewed)||2-5 mg|
Throughout the trial EEGs were recorded to demonstrate brain function, and blood flow through two key arteries was assessed as well.
So what did they see?
Well, acute caffeine abstinence lead to increased blood flow through those arteries which the authors suggest ties in with those severe headaches, which correlate with going cold turkey. This acute caffeine abstinence also led to changes in brain function as measured by EEG, associated with increased drowsiness and decreased alertness. Even the answers to questionnaires taken by the subjects show a similar effect, with increased ratings of words like “tired,” “fatigue,” “sluggish,” weary and decreased ratings of “energetic,” “friendly,” “lively” and “vigor.”
All of which fits with John’s description (and my own experiences when I switched back from strong coffee, to tea). And for further bad news the authors of this study, and others, report that daily intake and length of intake will also significantly worsen the effects of going cold turkey.12
Well, there you have it, as it turns out, caffeine withdrawal is caused by increased blood flow through key arteries in the brain, which causes pain in the form of headaches, and presumably dizziness for some people as well.
The more caffeine you drink, the worse the withdrawal will be.
If you’ve had an experience with caffeine withdrawal, we’d love to hear from you in the comments.