Stool Color Changes

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Definition of stool color changes

It is reasonable to have an obsession with one's bowel movements. The quality, quantity and color of stool may be an indicator of gastrointestinal system's health and should the stool change color, it may provide a clue as to what might be wrong.

Stool, feces, or poop is the waste product of digestion. Food mixes with bile from the liver and digestive enzymes from the pancreas allowing protein, carbohydrates, and fats in the diet to be broken down to form a slurry. This liquid mixture passes through the small intestine where nutrients are absorbed into the blood stream and the liquid waste is delivered to the colon. In the colon, water is absorbed and stool is formed. Normal stool contains bacteria, digested food, cellulose from undigested plant material, and bile.

Normal stool color can range from light brown to dark brown to green. Often the color of stool is affected by what has been eaten, and may not signify any potential illness or disease. However, it is possible that the color of the stool can provide important clues to an underlying disease.

What are the symptoms of stool color changes?

A diagnosis cannot be made by stool color. The patient and the health care professional need to consider other symptoms, past medical history, dietary changes, and medications to help decide what has caused the stool to change color. Physical examination will be important to help decide the significance of the stool color.

Stool may be tested to look for blood, fat or infection. Blood tests may be necessary depending upon the clinical situation.

Green stools

If stool passes through the intestine too quickly, there might not be enough time for bile to be digested and broken down to provide the normal brownish stool color. Bile is a greenish brown fluid that is manufactured in the liver and stored in the gallbladder. Bile helps digest fats in food. It takes time for the bile to degrade and turn brown in the intestine and if the transit time is short, the stool remains green colored. This is why diarrhea is often greenish in color.

Green stools may be a normal variant. It can also be caused by a diet rich in green vegetables, especially spinach. Iron supplements also may be a cause, though it often turns stool black.

Medically Reviewed by a Doctor on 9/30/2013

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It started with feeling a little run down after working extra hard, perhaps there was some lightheadedness when he stood too quickly, and then came the fatigue. The baseball world blamed Ichiro Suzuki's malaise on playing too much in the World Baseball Classic. During spring training, baseball players are supposed to lounge and gradually get themselves into shape, not play like it's the World Series in October. But the baseball world was wrong. It was discovered in April 2009 that Ichiro was tired because he was anemic and because he was bleeding from an ulcer.

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