NORMAL BOWEL MOVEMENTS
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A normal bowel movement should be some shade of brown, should be soft but still formed, and should be roughly the size and shape of sausage links, although this can vary with the softness of the stool. Your stool takes the shape of your colon. Foods and vitamins you eat can affect how your stool looks and smells, but so can diseases. Normal bowel movements DO NOT contain blood, and are not black or tarry.
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Frequency
There is no rule for frequency of bowel movements, but a good range is from 3 times a day to 3 times a week. Less than 3 movements a week may indicate constipation, and more than 3 watery stools a day could indicate diarrhea.
Size and shape
A bowel movement should be soft and easy to pass, though some people may have harder or softer stools than others. Stool should be brown or golden brown, be formed, have a texture similar to peanut butter, and have a size and shape similar to a sausage.
Constipation
Constipation is a very common problem and is estimated to be the cause for approximately 2 million doctor visits each year. Constipation is hard, dry, lumpy stools that are difficult or painful to pass that may be accompanied by discomfort. Chronic dehydration, lack of exercise, and low amounts of dietary fiber can all lead to constipation. Drinking enough water each day and avoiding caffeine can help prevent dehydration. At least 30 minutes of exercise (even brisk walking is better than no aerobic activity) most days of the week is recommended for better overall health. There should be enough fiber in the diet to insure that stools are soft and pass painlessly and easily.
Diarrhea
Diarrhea is loose, watery stools that occur more than 3 times in 1 day and, in most people, is a common problem that usually lasts a day or 2 and does not need any treatment. Causes include infection, side effects of medication, and food intolerance. Diarrhea may need treatment if it lasts more than 3 days and is accompanied by fever, severe pain or dehydration, or looks black, tarry, or contains blood.
Change in bowel habits
A normal bowel movement is different for each person and may vary in consistency and frequency. There are, however, several indications that a bowel movement is abnormal and may be the sign of a more serious problem. A change in bowel habits includes any constant change in bowel frequency, color, consistency, or shape of stools. This sign warrants special concern in people who are over the age of 50 years.
Blood. Blood in the stool is never normal, and could be a result of several conditions that range in seriousness from hemorrhoids to infection to colon cancer. Bloody stools should always be evaluated by a physician.
Black stools. Black, tarry stools with a foul odor can be the result of eating certain foods, taking iron supplements, or possibly from internal bleeding. {{Also a symptom of a problem with some medications}}
Red or maroon stools. Red or maroon stools could be from something benign, such as eating red colored foods or it could be caused by several different conditions including hemorrhoids, anal fissures, colon polyps or colon cancer, diverticular bleeding, and inflammatory bowel disease.
Green stool. Green stool may be caused by green or artificially colored foods, iron supplements, and decreased
colonic transit time.
Pale or clay colored stools. Stools that appear pale or look like clay could be the result of lack of bile salt (which gives stool a brownish color), antacids, barium from recent barium enema test, or hepatitis. {{Or a stone may be stuck in the bile duct of the gallbladder.}}