Hi, this is David from MinuteEarth. 87 double espressos are enough to kill you;
drink them all at once, and all that caffeine will short out your heart and stop it from beating.
Yet coffee shops are filled with plenty of not-dead people who have downed hundreds of
cups of coffee over their lifetimes. Here’s why: You can think of your tolerance for caffeine – or
any substance, really – as a bathtub; that tub holds the amount of that substance that can
circulate in your bloodstream safely at a given time. The more of that substance you take in,
the more the tub fills up - and the more effects you might feel, like the jitters from a series of
double espressos. But your body will keep humming along. That is, until the tub overflows…at that
point, the concentration of the substance in your bloodstream gets too high, and you’ll die.
Luckily for us caffeine lovers, like real bathtubs, our body’s poison tubs can drain.
As your body excretes potential poisons through pee and poop, or chemically converts them into
harmless - or even useful - compounds, the level of a substance in the hypothetical tub lowers.
Caffeine, for instance, gets metabolized by the liver into a buffet of organic molecules.
And it happens fast – the caffeine in one of those double espressos will drain from your
tub in a matter of hours. That's why you can drink pretty much as much caffeine as you want, as long
as you space it out. Cyanide - surprisingly - also drains quickly, as your body speedily converts it
to vitamin B12. So even though your cyanide tub is tiny, eating a few cyanide-packed apple seeds
every day is perfectly safe. Lead, on the other hand, leaves the body really slowly because it
gets stored in bones. So even though your lead tub isn’t tiny, since pretty much every lead exposure
throughout your life slowly inches the level in the tub upwards, it’s more likely to overflow.
These tubs exist for pretty much every substance we ingest - even water. If
you manage to guzzle more than 6 liters at once, your body’s water tub will overflow;
all that water will cause your cells to swell beyond repair. Luckily, that tub empties super
fast; not only does your body use water for pretty much every biological process, you can
also pee out any extra water within minutes. Now that’s what I call draining the main vein.
We love coming up with groan-inducing puns for our videos, and as we’ve expanded our
channel into other languages, it’s been awesome to see how those puns translate.
In order to truly appreciate them, though, I need something more than poorly-remembered
highschool Spanish, so I’ve started using this video’s sponsor, Babbel, to hone my skills.
The great thing about Babbel is that it teaches you using real life situations and conversations.
By practicing just 15 minutes a day for 3 weeks, I’ve managed to go from mumbling “hola”
to our resident Spaniard Arcadi to saying things like: “¿Qué hace el pez perezoso?
Nada.” To start conversing - and joking - in a new language today - and get 65%
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