On the mechanics of consuming liquids

[Duke87 1,070]

I had something interesting pointed out to me recently that I'd never realized before: I have a funny way of drinking.

Apparently, the normal method involves pouring liquid into one's mouth and swallowing it as it flows. I don't do this. I've attempted to do this since hearing about it and ended up spilling my drink all over myself and/or gagging on it. I just can't do it.

No, instead, my method involves a using a different bit of physics - not gravity, but pressure differentials. I tilt the glass/can/bottle/etc. just enough to bring the drink to the upper edge and then apply suction to draw it into my mouth from there... kinda like I'm using a straw, except not.

So, does anyone else drink this way or am I completely strange?

[Loney 22]

I think I remember trying it that way a few years ago by accident. Nothing feels better than getting water in your lungs and end up spending the next hour gagging and coughing up the water.

[astronelson 339]

I notice the way I drink can depend on the container and the temperature of the liquid. If I am drinking from a bottle, I will generally fill my mouth with water and then swallow it. If the liquid is in a cup and hot, I will use a similar method to what it seems you use. Most of the time I will drink by drawing the liquid into my mouth and swallowing it.

With this method, tongue positioning is key. If you have your tongue flat against the floor of your mouth, then drinking becomes more difficult and the gag reflex may come into effect.

This thread prompted me to have a closer look at the way I drink. Experiment time!

When drinking from a cup, I found that at the beginning of the liquid intake phase my tongue arches - the tip is on the base of the mouth behind the lower teeth, the middle of the tongue is against the roof of the mouth. In the swallowing phase, liquid flows around the tongue and is swallowed. I guess this mechanism has developed so that by changing the position and width of the tongue by small amounts, the flow of liquid can be regulated or cut off.

After this, I investigated the mechanism I use to draw liquid into my mouth. I had originally thought that the liquid was drawn into the mouth by expansion of the cheeks, but experiment proved otherwise. Consciously attempting this showed it was actually a rather difficult method. The true mechanism seems to be the tongue receding. From the tongue receding, pressure in the mouth is reduced a small amount, drawing liquid into it. Breathing through the nose simultaneously is possible. It seems the tongue acts again to stop the liquid entering the pharynx. Investigating further, I found that the back of the tongue arch meets the cheeks, closing off that route.

When swallowing, the trachea is closed off, the tongue breaks contact with the cheeks and the liquid is free to be swallowed. The front of the tongue blocks off further liquid intake during this stage.

So, it seems my method of drinking follows these steps:

1. In preparation for liquid intake, the tongue arches in the mouth and expands at its rear, blocking off the pharynx. The trachea is opened.
2. Liquid is brought to the lips and the tongue recedes in the mouth, drawing liquid into the oral cavity through reduction in pressure.
3. The trachea is closed off.
4. The tongue contracts at its rear, allowing liquid to flow into the oesophagus. The front of the tongue expands to block further liquid intake.
5. After the liquid in the mouth has been swallowed, the cycle repeats from step 1. Some liquid may remain in the mouth at this stage.
6. When all the liquid in the vessel has been consumed, a few more swallows may be made to remove any liquid remaining in the mouth.

[CHR 2]

I drink the same way as Duke - by sucking the water into my mouth and then swallowing it from there. That said, I can (though usually don't) drink by pouring the liquid into my mouth and then swallowing, the way you might drink if you were drinking from someone else's drink (not wanting to touch the cup).

Interestingly, if I pretend to drink, I notice I breath in as I tilt the glass. I've tried pouring the water in, and seem completely incapable of doing so.

[A Nonny Moose 8,262]

Whatever works, depending on the temperature of the liquid, and the container.  Chugging directly to the esophagus is possible with certain cold liquids, but I don't recommend it because you can easily pour something down your air way with alarming, if not fatal, results.  I dont 'have a very strong gag reflex, but it can be triggered by trying to guzzle a beer, for instance.

Any astronauts present?  How do you swallow liquids in zero g?.

[CHR 2]

I believe when you swallow the muscles lining your esophagus contract in sequence to push the substance within down - it is not done by gravity. That said, I would still be difficult with water I should think.

Although it doesn't explain how it is done, this shows an astronaut drinking seemingly normally (and explains how to make a cup in space) - http://www.neatorama.com/2008/11/25/drinking-coffee-in-space/