20 things you didn't know about caffeine

Without the world's favorite stimulant, every morning would be like a Monday morning. But despite humanity's utter dependence on caffeine to keep us from yawning in the middle of important meetings, most people's knowledge about this humble alkaloid starts and ends with working the K-Cup machine.
So to salute this wonder drug, we've compiled 20 things you didn't know about caffeine, ranging from legends about goat herders to how it affects your brain. Pro tip: drink a cup before you read on and you might remember these better.

1. It's the fourth most widely used drug in the world
According to the 2014 Global Drug Survey, "caffeinated energy drinks" are barely edged out by marijuana, which claimed the bronze medal for consumption. Tobacco came in second, while alcohol leads the pack. "Mystery white powders", on the other hand, still remain towards the bottom of the pack, and clearly need an image makeover.
2. Caffeine first entered the scientific canon in 1819
German chemist Friedlieb Ferdinand Runge was the first to identify the chemical, which, according to Today's Chemist At Work magazine, was isolated from rare coffee beans that were a gift from the writer Johann Wolfgang von Goethe. Also, there is a magazine called Today's Chemist At Work.
3. The three most popular drinks in the world all contain caffeine
Coffee, tea, and cola.
4. It works by blocking inhibiting brain juice and increasing dopamine
Adenosine is a chemical that accumulates in your brain over the course of the day and makes you tired. Caffeine so closely resembles adenosine that it blocks the adenosine receptors, keeping your brain from feeling fatigue. Plus, there's a kick of that all-important pleasure spiker known as dopamine. Both of these chemical reactions happen in the prefrontal cortex, which is generally associated with planning cognitive skills.

5. According to legend, we owe a great debt to an Ethiopian goat herder named Kaldi... or a Yemeni dervish named Omar
The prevailing myth of coffee's origin states that the bean was discovered after Kaldi, a herder, noticed his goats dancing around while high on coffee berries. The plot line splinters from there, but the most common version states that he then brought the beans to an Islamic monk who objected to them on religious grounds and threw them in a fire... where they were roasted and ultimately used for the first very coarsely-ground cup of Joe.
The second legend involves a Yemeni dervish named Omar who had been exiled from the city of Mocha (this city gives one variety of bean its name) and found a coffee bush while starving in the desert. He roasted the beans in water, drank it, and then was so revitalized he began spreading the gospel of caffeine as a miracle cure.
6. Caffeine takes 20-30 minutes to go into effect
To maximize the benefits, take a quick nap immediately after consumption in order to lower your adenosine count and give that caffeine more receptors to hook up to. The half-life of the drug is four to six hours, and most often your system is relatively clear after 12 hours.
7. It's not just in coffee beans or tea leaves
You can also find caffeine in cola nuts (used in... colas), cacao beans, and the guarana fruit.

8. Roasting coffee beans decreases the amount of caffeine
That's why darker roasts generally have lower caffeine levels.
9. Smokers synthesize caffeine more quickly
The same enzyme that breaks down nicotine also breaks down caffeine, so the excess of it allows smokers to metabolize caffeine twice as fast as non-smokers.
10. There is more caffeine in espresso than coffee per milliliter
But since the serving size is so much larger, drip coffee almost always has more caffeine overall than a shot of espresso.
11. Tea leaves have higher caffeine content than coffee beans
But due to the weaker style of brewing, tea is usually much less caffeinated. Tea is also loaded with tannins, a molecular compound that slows the absorption of caffeine.

12. Caffeine has a taste
If you've ever tasted crushed Aspirin, you've got a good idea of what caffeine tastes like. Partly because Aspirin is often cut with caffeine to increase effectiveness, but also because they both taste really bitter.
13. The FDA says Americans consume 300 milligrams of caffeine per day
To give this some context, the caffeine stats from Caffeine Informer equate this to 14oz of Starbucks.
14. The US buys the most coffee overall, but the Netherlands has the highest per capita consumption
According to Datahero, the Dutch consume more than twice as much coffee as Americans per capita... maybe because they've got all those great coffee shops.

15. You can smoke it, but probably shouldn't
According to our best bros at Supercompressor, it might make you feel like you have rabies and your heart is about to explode.
16. Europeans first got their caffeine from chocolate, not coffee or tea
According to The World of Caffeine, chocolate brought across the Atlantic by Spain became popular about 50 years before coffee or tea.
17. When coffee companies decaffeinate their beans, they don't just throw away the caffeine
Decaffeinating coffee is a complicated process that has oblique ties to the Third Reich. But once that caffeine is taken out, there's a lucrative caffeine marketplace out there thanks to the proliferation of energy drink companies, according to our sources at Coffee Chemistry.

18. Caffeine content varies widely among coffee brands
Starbucks has over twice as much caffeine as McDonald's, as shown in this delightful infographic.
19. You can be allergic to it, and too much can kill you
Many of the signs of an allergic reaction are just uncomfortable side effects like jittering or inability to sleep, but some people can actually break out in hives or hyperventilate. Those with a normal caffeine tolerance shouldn't have to worry too much about overdose: according to AsapSCIENCE, you'd need to drink 70 cups -- at once.
20. It has a positive effect on longterm memory
In a study at Johns Hopkins, test subjects were administered doses of caffeine and shown a series of images. When tested again 24 hours later, they displayed signs of improved pattern recognition.
Dan Gentile is a staff writer on Thrillist's national food and drink team. While writing this at a coffee shop, he explained to someone he was working on a story about caffeine. They thought it was a joke. Follow him to more accidental humor at @Dannosphere.