Re: Why do we get hiccups?

That is a good question.  I'm sure people have been asking that question 
since before recorded history.  And you know what? We still don't know.  
That is, no one knows for sure.  After reviewing 192 scientific 
references, one researcher concluded, "The purpose of the hiccup is 
unknown".  

In my search I repeatedly found answers like the one given by Jethro Kloss 
in his book "Back to Eden" ... Causes: "Irritation of the phrenic nerve, 
resulting in contraction and spasm of the diaphragm. Excessive food or 
drink in the stomach."

There is no question that a hiccup is a contraction of the diaphragm (the 
muscle that controls breathing between the lungs and the abdominal area).  
And since the diaphragm is controlled by the phernic nerve, it is most 
assuredly involved as well.  In fact, if you cut the phrenic nerve, there 
are no more hiccups.  But what does that have to do with overeating, or 
drinking too much alcohol, or eating too fast (some things thought to 
sometimes cause hiccups)?  In other words the real question is, "why do we 
hiccup?"  What, in the course of our evolution, made it possible for those 
who hiccup well (whatever that is) to survive over those who didn't 
hiccup?  It is very possible that the hiccup is a remnant from a very 
distant evolutionary past that has no use anymore and may not even be the 
same thing it once was.  Or, it may server some yet unidentified purpose.

The best and most extensive discussion I found on the Internet was this 
one http://www.inxpres
s.net/~oastiennon/webdoc21.htm by Dr. O. Arthur  Stiennon.  Although 
somewhat technical, this is an excellent discussion of hiccups including 
some 26 scientific references. Dr. Stiennon contends that hiccups are used 
to get excess gas out of the stomach (much like a burp) but do so in a 
manner that would prevent stomach contents from getting into the lungs.  
This could be thought of as the evolutionary advantage that evolved the 
hiccup, but I did not come across any others who seemed to take Dr. 
Stiennon's point of view.

One thing is for sure, there are a lot of ways to cure them.  Here is a 
list of some cures I came across.

"A woman was once brought to me who was nearly dead from hiccoughs. I gave 
her the juice of half an orange and the hiccoughs stopped immediately. The 
juice of an orange will usually stop hiccoughs."
Chew gum
Blow on your thumb
Put peanut butter on the end of your tongue.
Take a spoon of sugar
Suck on a lemon
Take a tablespoon full of vinegar
Chew & swallow dry bread
Gargle with water
Hold your breath 
Suck on crushed ice 
Tickle your nose until you sneeze
Drink water fast 
Drink water slowly
Drink water with your nose plugged
Drink water with someone’s fingers in your ears
"Take three deep breaths and hold the last one as long as you can. Then 
blow the air out as if you were whistling. Done properly, it never fails."
And my personal favorite: "Tell someone, 'I will give you $5 if you hiccup 
again right now'." Apparently, this one really does work every time. :-)

Thanks for the question.  It has been answered a couple times already here 
on the Mad Science Network.  For those answers and other related to 
hiccups, and sneezing see this link to our FAQ page.  http://www.madsci.org/FAQs/
body/hsy.html

Dave Leonard, MD
Navy Flight Surgeon