Parents spend the first few years of their child's life immersed in a world of poop. You learn what's "normal" and what's "abnormal" for your child. But, as they graduate from potty training, you may miss out on a very important measure of your child's health: the color of their poop.

As part one of a two part series, let's delve into the world of poop.

So, what is poop in the first place? About 75% of poop is water, and the remaining 25% is made up of a variety of waste that is being eliminated from your body: undigested food pieces, bacteria (both dead and live), fiber, mucous and proteins and salts.

What is normal when it comes to color? The ideal color is a brown that is similar to plain cardboard. This normal brown color occurs because of bilirubin, which is formed when red blood cells break down in the liver. Bilirubin is green as it is secreted into bile and turns brown after it enters the large intestine.

But, there are a number of other factors that influence the color of your child's poop, the most common of which is diet. Below are some reasons for color changes. If the change in color occurs in more than one stool, it's important to see your pediatrician because it may signal the presence of a medical condition.

Red or Black:
Reddish stools can be an indicator of eating a significant amount of food with red coloration, like beets, cherries, red gelatin, red Kool-Aid and tomato soup. Black stools may occur in response to certain medications, such as iron pills or bismuth (found in Pepto Bismol), or foods like licorice, Oreo cookies and grape juice. If your child continues to have black stool, it may be due to bleeding, which can occur for several reasons. Black or bloody stools are a signal to visit your child's pediatrician. If your child is constipated and straining, they often experience blood in stools. Other culprits include bleeding from hemorrhoids, the upper gastrointestinal tract or an ulcer.

Green:
Green poop may be caused by excess iron in your child's diet. If they don't digest all the iron, it actually stains the poop green. Green, leafy vegetables contain chlorophyll which could be coloring the stool green, as could green gelatin.

Sometimes green stool occurs when the child has diarrhea. If stool passes through the large intestine too fast to change in color, it may result in green poop.

Yellow-white:
When poop is yellow-white, it's sometimes because of antacids or excessive milk consumption. However, it may also indicate problems with the gallbladder or liver. If stool is also shiny or greasy, floats and has a strong odor, it may be caused by undigested fat.

Remember, if your child experiences a prolonged change in the color of his or her stool (more than a couple of stools), it's important to talk to your pediatrician. Click here for a downloadable chart that you can use to help track your child's bowel movements.

Part II: What does the shape and consistency of stool say about your child's health? >>

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