The Doctor's In

Fact Monster asked pediatrician Dr. Brian Orr to answer some questions kids commonly ask about their bodies. Dr. Orr, whose office is in Gloucester, Massachusetts, has practiced medicine for more than 22 years. A father of three kids, ages 16, 13 and 8, Dr. Orr is also a writer and columnist.


[CENTER]Why do we sneeze? [/CENTER]

We sneeze to clear our breathing passages. We all have a natural reflex to sneeze whenever a small foreign substance enters our airways. So don't hold back your sneezes-let 『em rip!


[CENTER]What happens when my foot falls asleep? [/CENTER]

Feet don't really sleep. They just feel tingly when an adequate blood supply to our nerves is cut off. This usually happens when you stay in one position too long―like sitting with your legs crossed. It just goes to show that it's good to keep your body moving.


[CENTER]Why does my nose run?[/CENTER]

The nose serves as one of the body's first barriers against infection. Your nose makes more mucus when a foreign substance, such as a virus, enters the body. The increased mucus, combined with increased blood flow to the nose due to an infection, causes your nose to "run" with excess liquid. And it keeps tissue companies in business.


[CENTER]Why do we shiver?[/CENTER]

When we shiver, our bodies are doing the opposite of sweating. Sweating cools the body by putting a layer of liquid on the skin. Shivering tightens the skin and shakes the muscles, a process that conserves and generates heat. You can stop your shivering by bundling up―just like your mother says.


[CENTER]Why does a bruise turn colors?[/CENTER]

A bruise is actually a pocket of blood under the skin caused by a broken blood vessel. It changes color and fades as the body reabsorbs the blood from the bruise.


[CENTER]Why do our temperatures rise when we are sick?[/CENTER]

Temperatures rise in our bodies to fight infections. Fevers create an environment that, we hope, is too warm for the invading organisms. Turning up the heat makes viruses and bacteria feel unwelcome.


[CENTER]How does a scab form?[/CENTER]

Scabs patch up holes in the skin. Certain cells in our bloodstream recognize when our skin has been broken. These cells, called platelets, start patching the break in the skin and call in other blood components to help complete the process. They do an amazing job. Don't make your platelets work overtime by picking your scabs!


[CENTER]How do bones grow?[/CENTER]

Bones are made of a network of calcium laid down by cells. As kids grow, special cells at the end of bones add new calcium to the network of bone. Children have layers of these cells in the shape of plates at the ends of their bones. These are called "growth plates," and they close up when kids reach their full adult height.


[CENTER]Where does ear wax come from?[/CENTER]

Ear wax is made by skin glands near our ear drums. The wax protects the ear canals and acts as a barrier against bugs and bacteria. Only in cartoons can it be used for candles!


[CENTER]What causes a burp?[/CENTER]

When we eat, we swallow air with our food. Our stomach already has air in it from bacteria that produces gas and from chemical reactions caused by digestive enzymes. When there is too much air to fit in our stomach, we force some out in what we call a "burp." It's funny that something considered impolite occurs so naturally.


[CENTER]Is a healthy person's temperature always 98.6F?[/CENTER]

Healthy or sick, our temperatures change throughout the day. Our temperatures cycle up and down in a rhythm. When we are healthy, our average temperature is 98.6F, but even when we are healthy our temperature could go up to 99F or down to 97F. When we are sick, our temperatures cycle to higher points. Someone has a fever when their body temperature is over 100.5F, so a temperature of 99F is not a reason to stay home from school!


[CENTER]Are "low-carb diets" good for kids?[/CENTER]

No diet is good for kids. You may have heard about some fad diets such as the Atkins Diet or the South Beach Diet. Adults follow these diets to lose weight. Most diets work at the beginning, but it's hard for adults to keep the weight off over a long period of time. As for kids, no diet is as effective as eating sensibly. You also need to exercise each day to keep you healthy and trim. So turn off the TV, get up and be active and eat your fruits and vegetables. Do I sound like your mother?


[CENTER]Why do some people have "innies" and some have "outies"?[/CENTER]

Many mothers ask me if their babies will have an "innie" or an "outie". I can tell by how much skin grew out from the baby's body toward the umbilical cord. As the cord falls off, the baby is left with extra skin hanging from their "outie" belly button. Babies whose skin doesn't grow out toward the umbilical cord are left with very little extra skin on their bellybutton, an "innie." Do you have an "innie" or an "outie"?


[CENTER]When I get a sore throat why does the doctor stick that wood thing down my throat?[/CENTER]

Sore throats are usually caused by viruses. But some are caused by bacteria called streptococcus. When this happens, we say the person has strep throat. Doctors use the stick to push your tongue down (and have you say "ahh") so we have a better view of your throat. We're looking for redness and white patches on the tonsils. Sometimes it's hard to tell if you have strep by just looking, so the doctor swabs your throat to remove some of the infection. We check the sample in the office to determine if you have strep. We also send it to a lab to double check. It's important to treat the infection so it doesn't spread to other parts of your body-like your heart.


[CENTER]Why do we get body odor?[/CENTER]

Most people think we get body odor from sweat. But that's only partially true. Much of our body odor comes from bacteria that live on us and grow in our warm sweat. When bunch of bacteria clings together in close quarters, it emits an unpleasant odor. When we bathe, we wash away the bacteria―and the smell.


[CENTER]Why do we blink?[/CENTER]

Blinking protects our eyes from foreign objects, sweeps up dirt that gets in our eyes and lubricates our eyes by spreading tears across the surface. Don't you think that is a lot to accomplish in the "blink of an eye"?