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Weird Things The Body Does: Why We Hiccup, Yawn, Itch and More

by Laura Picciano, D.O. woman-laughing-glasses-red-hair

Ever find yourself wondering why your body did something strange? Well, even the most bizarre responses are a complex interaction of nerve, brain and muscle functions. Some may make sense to you, while others are just plain odd.

So here are some explanations for why we do things. Click on a weird thing below or just scroll down.

Hiccups are caused by muscle spasms. They’ve been known to last for days, even years! They mainly involve two body parts: the diaphragm and the epiglottis.

  • The diaphragm is a dome-shaped muscle that separates the chest cavity from the abdomen. It helps you breathe in by flattening and creating a vacuum.
  • The epiglottis is a piece of tissue that closes over the windpipe when you swallow, keeping you from inhaling food and saliva.

When the diaphragm gets irritated, it spasms, causing you to breathe in quickly. Your epiglottis tries to snap shut, and you get that famous “hic” sound.

The causes of hiccups include a long list of common and even scary things. Certain brain and spinal-cord diseases can cause persistent hiccups. But fortunately, most of the time the culprit is simply an irritant to the area around the diaphragm—a result of overeating or alcohol consumption, for example. Fear or stress can also bring them on.

Most cases are brief and require no treatment at all. And there are a million home remedies. Just ask a friend!

ice-cream-cone-headacheWHAT CAUSES BRAIN FREEZE?

Watch out, ice-cream lovers! When you take a big bite or sip of your favorite frozen treat, you may be in for an unpleasant surprise. Within seconds, an intense pain can develop in the middle of your head—also known as a brain freeze, or an ice cream headache.

What’s happened, is the cold food has caused sensitive nerve endings in the roof of the mouth to fire a message to the brain that it may get a cold spell. To prevent a threatened drop in temperature, the blood vessels try to warm the brain and temporarily swell, causing the horrible yet short-lived sensation.

To prevent brain freeze, let your warm tongue touch the roof of your mouth, and don’t eat or drink so fast!


Sneezing is the body’s way of cleansing the nasal passages of harmful things like germs and irritants. It happens like this:

  1. When you inhale debris that irritates your nose’s lining, nerves send a signal to the brain to clear the passageway.
  2. The brain fires a signal to the chest and diaphragm, telling them to blast out some air.
  3. At the same time, the brain tells the throat to close up.
  4. Instead of escaping through the mouth, much of the air goes through the nose, dislodging the particles. Like dynamite, out comes a great big sneeze!

Think of it as an advanced air purifying system.

skeleton-window-laughingWHY DOES MY FUNNY BONE HURT?

The funny bone is not a bone. It’s a nerve—the ulnar nerve, to be precise, which runs from the neck to the hand and then into the ring and little fingers.

At your elbow, the ulnar nerve is exposed. Striking it sends a shock wave down the arm. Although the mild thump causes no damage, it sure feels weird and may cause others to laugh at you. Perhaps that’s why it’s so funny!


Even though both people and animals yawn, we don’t completely understand the phenomenon.

A yawn is a reflex in which your mouth opens, you inhale deeply, and then you slowly exhale. The overall effect is a release of carbon dioxide and a sudden increase in oxygenation, which raises our heart rate. So some people think yawning is simply a way to increase alertness. Others contest that idea, though, and have proposed their own—like yawning is a form of stretching. No theory has yet been proven.

To confuse things even more, for some reason, yawning occurs more often in folks with certain types of brain damage and multiple sclerosis. And, how funny, even fetuses in the womb have been seen yawning!


When you're cold, your body sends signals to your brain, which in turn sends signals to your muscles, telling them to contract and relax rapidly. This helps produce energy and thus raise the temperature. It's what you feel as shivers, or chills or rigors.

But when you're not exposed to cold and get the chills anyway, they’re usually heralding the onset of a fever. During an infection, chemicals from the white blood cells (infection fighters) send a message to a part of the brain called the hypothalamus. This center acts as the body's thermostat. The hypothalamus turns up the body’s set temperature. (We’re not sure why it does this, but we think it’s part of your body’s attempt to fight off the invading organism.) This thermostat raise makes your body think it needs to be warmer, so it responds with chills.

hissing-coon-cat-goose-bumpsWHAT CAUSES GOOSE BUMPS?

All mammals are capable of having goose bumps, or chill bumps. Have you ever seen a cat get angry and fluff up its body? That’s basically its version. We do it as a reaction to cold and often fear and anger.

When your body feels cold, it tries to conserve heat by closing up the pores. It does this by constricting tiny little muscles at the base of the hairs that exit the pores. This causes the hair to stand on end. It also forces out a tiny amount of oil, which may help trap heat.

Hair fluffing, especially in animals (who have more of it), traps warm air and forms a barrier between the cold environment and the skin. In defense situations, hair standing on end causes the animal to look larger and more imposing, thus scaring away a predator.


Annoying and sometimes painful, muscle twitches can occur anywhere in the body. They’re particularly common in the eyelids. We’re not sure why they happen, but overstimulation of the nerve that controls the particular muscle group could have something to do with it.

Muscle twitches are generally nothing to worry about. Overuse, strain, emotional stress and even too much caffeine can cause them. Prolonged twitching, however, could be caused by more serious conditions that require medical attention.

legs-toe-socks-itchWHAT CAUSES ITCHING?

Your skin is the largest organ in your body. And inside that organ are special cells that contain a protein called histamine. The cells release histamine when you come into contact with an allergen (something your body thinks is dangerous, whether it really is or not). The histamine reports to a special center of the brain that causes us to scratch—sometimes to the point of raw skin!

Your skin also contains nerve fibers dedicated to the itch sensation. Irritants like dryness, bacteria and insects can activate these nerves.


Joints pop for a couple of reasons—one of them being gas (but not that kind).

Joints are surrounded by a lubricating fluid and encased in a capsule. When you bend them far enough, gasses dissolved in the fluid separate out and make a tiny bubble. When the bubble pops, you hear a cracking sound.

newsletter-graphicOther times, though, that sound is not from gas but from tendons (which connect muscle to bones) or ligaments (which connect bones to bones) moving into a new position.


So now you know a secret or two about your wonderful body. But just think of all the mysteries left to discover. It looks as if we’ve only just scratched the surface! Then again, that’s nothing to sneeze at.

OK, I’ll stop.

, is a board-certified internist at Hahnemann University Hospital in Philadelphia.

Last updated and/or approved: June 2010. Original article appeared in summer 2007 former print magazine. Bio current as of summer 2007. This article is not meant as individual advice. Please see our disclaimer.


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