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Causes of Constipation
There are many possible causes of constipation. For example, the most common causes include lack of exercise and insufficient intake of fiber or liquids. Some other things that can lead to constipation include certain medications, a few specific diseases, and problems with the colon and rectum.
To understand the causes of constipation, it helps to know how the colon (large intestine) works. As food moves through the colon, the colon absorbs water from it while forming waste products known as stool. Muscle contractions in the colon push the stool toward the rectum. By the time it reaches the rectum, the stool is solid because most of the water has been absorbed.
The hard and dry stools of constipation occur when the colon absorbs too much water or if the colon's muscle contractions are slow or sluggish. Slow contractions cause the stool to move through the colon too slowly, allowing too much water to be absorbed.
Factors that can contribute to constipation include:
- Not enough fiber in the diet
- Not drinking enough liquids
- Lack of exercise
- Some medications
- Irritable bowel syndrome (IBS)
- Changes in life or your routine, such as pregnancy, older age, and travel
- Abuse of laxatives
- Ignoring the urge to have a bowel movement
- Specific diseases, such as a stroke (by far the most common)
- Problems with the colon and rectum
- Problems with intestinal function (chronic idiopathic constipation).
Written by/reviewed by: Arthur Schoenstadt, MD
Last reviewed by: Arthur Schoenstadt, MD