My Friend Can Swallow Upside Down

A friend of mine says he has found

that he can swallow upside down.

I’m wondering if this is true,

and could I somehow do it too?

Please, Dr. Jo, this bothers me.

I just don’t know how it can be

that if I’m standing on my head,

food won’t go down, but up instead.

Yes, you can swallow on your head,

or lying flat upon your bed,

or even while you sleep at night.

The swallow reflex gets it right.

Your swallows are amazing things,

’cause normally each gulp will bring

food into the exact right place:

your stomach’s empty, waiting space.

A swallow’s complicated, though,

cause there are ways food shouldn’t go.

Like out your lips, so it flies straight

back through the air, onto your plate.

Or to the trachea: that’s where,

each time we breathe, we take in air.

Food shouldn’t go there—it’s no joke,

’cause if it does, you’ll start to choke.

A third wrong route is one that goes

directly up into the nose.

It does sound gross (but it’s quite rare

for swallows to send food up there).

To get it right, a swallow must

close all but the esophagus.

It makes the tongue rise up so that

the ball of food gets pushed on back.

The next step is to quickly close

the pathway leading to your nose,

raising the uvula: a flap

that dangles in your mouth, way back.

And last it moves another flap:

the epiglottis, which will cap

the trachea. All this will make

a single path for food to take.

Now food can move without much fuss

right into the esophagus.

Once there, your food won’t hang around;

the next place it will go is down.

But chewed food needs assistance to

squeeze down the tube the whole way through,

cause this food tube is small inside—

it’s hardly more than one inch wide.

So the esophageal wall

contracts, and forces food to fall

with peristaltic waves that push

all of the chewed-up, swallowed mush.

These waves ensure that food will go

into your stomach down below.

And if you’re standing on your head,

these waves make food go up instead.

But if you laugh or gasp, that may

make swallowed food move the wrong way.

So laugh, then swallow. That is best.

Don’t put that reflex to the test!

COOL FACTS ABOUT SWALLOWING

• Sloths always do their swallowing upside down. These large, furry mammals eat while hanging from tree limbs; they will hang upside down for four to six hours a day, munching on leaves. Since all the hanging sloth’s organs are above its head, the sloth must swallow everything up instead of down.
• Flamingos also normally swallow up instead of down. These large birds feed by placing their hooked beaks upside down into the mud of a shallow lake. There, they filter out hundreds of tiny organisms called “plankton” from the water. Then they swallow the plankton up their long pink necks and into their stomachs.
• One thing that happens when you swallow is that your tongue moves to the roof of your mouth. Since this is part of a reflex—a process your brain makes occur without your thinking about it—it’s very hard to prevent it. Try swallowing some saliva while holding your tongue down on the floor of your mouth. You can do it, but you’ll find that it’s very difficult.