I Tried 5 Different Coffees for 5 Days. Here's What I Learned About Caffeine


Waking people up is big business, and there are now more coffee options than we know what to do with.

Coffee sales in the United States alone hover around $30 billion every year. You might drink coffee throughout the day, or just have a small cup with breakfast; you might truly love the taste and smell, or see it as a necessary evil. Regardless, coffee has long been humanity's drink of choice for one key reason: caffeine. 

But with all the options out there (cold brew, pour-over, old-school drip and even coffee with butter), choosing the best source for your caffeine addiction isn't as easy as just perusing a single cafe menu. Spurred by Starbucks' recent introduction of the flat white (do we really need more Starbucks options?) and the continued obsession with the calorific Bulletproof coffee, I set out to find the java that delivered the best bang for my buck — or rather, the most effective caffeine jolt with the least amount of jitters, all in the tastiest, most efficient form. 

Lately I've been avoiding home-brewed joe because it never tastes as good as the stuff from the store. But for the test, I went back to coffee boot camp for five days straight, seeking out the best taste, but also the best caffeine experience. After all, it's the reason we drink coffee, plus it's good for our brains. Waking at 7 a.m. every morning, I brewed, blended and broke down the results to find the ultimate cup of coffee. Here's what I learned.

Monday: Plain drip coffee

Caffeine: 20mg per fluid ounce


Effort: This one took an old-fashioned drip coffee maker. Because I underslept the night before, the wait for that first cup of coffee was the longest three minutes of my life.

Taste: Although I'm usually underwhelmed by the coffee I make at home, this morning's cup was delicious. It may have had something to do with the exhaustion I knew each cup would immediately alleviate. 

Alertness-to-jitters ratio: The third cup of coffee may have been a mistake. The coffee was just so warm and inviting (and free!) that I drank too many cups before realizing I'd gone too far. I quickly went from pleasantly awake to jittery, which was basically my system stressing out. My body was still exhausted while my brain felt like it needs to do 100 jumping jacks. I was alert, but with serious jitters. The coffee was cheap and easy, but with a less than pleasant result.

Tuesday: Espresso

Caffeine: 51mg per fluid ounce


Effort: I'll admit: Since I don't have an espresso machine at home, I rallied myself over to the nearby coffee shop and got a double espresso to go. If you have a proper espresso machine, it takes much less time than brewing a cup of coffee. Yet making a cup with an on-the-stove model ends up being an equal time commitment. Buying? Also pretty easy, but not cheap. 

Taste: Though I like coffee, espresso tends to be bitter. It's hard for me to sip it like you're supposed to, so I waited, let it cool and downed it as fast as I could. It's like taking caffeine medicine.

Alertness-to-jitters ratio: It didn't take quite as long as on Monday for the overall wide-awakeness to kick in. The jitteriness I had felt before was nonexistent. It probably helped that I was limited to a double shot. I felt awake throughout the day but without that my-heart-might-explode feeling that too much coffee can give me.

Wednesday: Turkish coffee

Caffeine: 30mg per fluid ounce


Effort: I tried my best to make Turkish coffee but will admit that there are a few big differences between my version and the true, traditional style. The general definition of this brew is a strong cup served with the grounds in the cup, but crucial to the taste is also using a very fine blend of coffee (even more powdery than espresso), which I didn't have. And instead of boiling water in the small copper pot known as an ibrek, I had to use a small pan. Despite the two glaring differences, what I got to sip was indeed a very strong cup of coffee with grounds in it. Mission accomplished, with a bigger-than-usual amount of effort.

Taste: You'd think that if I found the espresso bitter, coffee with actual grounds would be unpalatable. But Turkish coffee, when done right, is surprisingly sweet, almost like what I've been served in Istanbul. As long as you let the grounds settle to the bottom, the coffee itself is quite smooth.

Alertness-to-jitters ratio: This stuff is strong. I got about halfway through one cup of coffee before the jitters started coming on. It's ideal if you need to wake up in a hurry, but I'm not sure if I could sip on this all day. If you're the type of person who depends on coffee breaks to get through the work day, something a little weaker might actually be better.

Thursday: Instant coffee

Caffeine: 7mg per fluid ounce


Effort: To make instant coffee, you boil some water and pour it over dehydrated coffee-colored lumps in an effort to transform the sand-like grains into a smooth, fragrant cup. What I got instead smelled a bit like wet cardboard. With any cup of coffee, the most time-consuming step is heating the water. Despite eliminating the need to brew, instant doesn't shave off more than a few minutes overall.

Taste: As far as taste, liquefied packing peanuts would make a solid comparison. At least the coffee color is right, which almost makes it more disconcerting. I took a second sip in case it had gotten better. (It definitely had not.) I imagine this is what early tests of the poo-into-water machine tasted like.

Alertness-to-jitters ratio: Though there are supposed to be brands of instant coffee that don't taste like old cafeteria food, the one I chose clearly wasn't on the list. Even worse, the brew was weak and never really did much to wake me up at all. If you do decide to bring instant coffee into your home, make sure it's the good stuff. Half the world drinks it, so it can't all be bad.

Friday: Bulletproof coffee

Caffeine: 18mg per fluid ounce


Effort: Putting butter into your coffee seems weird, especially when you see how much you need to make a cup of Bulletproof (1 to 2 tablespoons for every 1 to 2 cups of coffee). Between making a cup of coffee and mixing in butter in a blender (not to mention the time it takes to clean oily coffee out of your blender afterward), this is not a quick beverage. But if you think of it as a meal replacer, you may save time in the morning.

Bulletproof's inventor, Dave Asprey, promotes the beverage as both a breakfast-replacer and a brain-booster, in addition to providing a nice caffeine jolt. I decided to skip my morning meal to test out Asprey's theory. If you choose not to, the Bulletproof police won't come and get you. We think.

Taste: It's surprisingly delicious. The texture of the butter-foam on top reminds me of a whole milk latte, only instead of steamed milk it's pure, unadulterated fat. Has putting butter into anything ever made it taste worse?

Alertness-to-jitters ratio: Surprisingly, this worked. I was hungry; deciding you're not allowed to eat in the morning is the best way to make food the only thing you can think about. But other than the constant desire for an omelette, I felt jitter-free, and I didn't feel the need to take a mid-afternoon nap. That extra midday boost of energy may have more to do with finally eating lunch than the coffee's long-lasting energy boost.

The verdict: 

The key to a positive coffee experience comes down to how and when that caffeine kicks in, and that depends on how much you need to drink... which in turn depends on how good it tastes.

Instant coffee tastes like garbage, drip coffee requires so many cups it made me jittery and turkish coffee is delicious but hard to make. Espresso is a caffeine godsend and is efficient, but leaves something to be desired in the taste department.

But Bulletproof Coffee? As much as I hate to give into a fad, buttered coffee made a good case for itself. The high calorie content of Bulletproof makes it harder to sip it like any other beverage, meaning I got all the energy throughout the day without any of the jitteriness. And its unfair buttery advantage also made it the clear winner in terms of taste.

The lesson here might not be to jump on every coffee trend (sorry, Starbucks flat white). But hey, it might be worth trying. The world will never grow tired of trying new coffee varieties. Plus, science says it's good for you — and that's good enough for us.