Diseases
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Constipation

Constipation is passage of small amounts of hard, dry bowel movements, usually fewer than three times a week. People who are constipated may find it difficult and painful to have a bowel movement. Other symptoms of constipation include feeling bloated, uncomfortable, and sluggish.

Many people think they are constipated when, in fact, their bowel movements are regular. For example, some people believe they are constipated, or irregular, if they do not have a bowel movement every day. However, there is no right number of daily or weekly bowel movements. Normal may be three times a day or three times a week depending on the person. In addition, some people naturally have firmer stools than others.

At one time or another almost everyone gets constipated. Poor diet and lack of exercise are usually the causes. In most cases, constipation is temporary and not serious. Understanding causes, prevention, and treatment will help most people find relief.

What Causes Constipation?

To understand constipation, it helps to know how the colon (large intestine) works. As food moves through it, the colon absorbs water while forming waste products, or stool. Muscle contractions in the colon push the stool toward the rectum. By the time stool reaches the rectum, it 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. This happens because the colon’s muscle contractions are slow or sluggish, causing the stool to move through the colon too slowly. Figure 2 lists the most common causes of constipation.

Common Causes of Constipation

  • Not enough fiber in diet
  • Not enough liquids
  • Lack of exercise
  • Medications
  • Irritable bowel syndrome
  • Changes in life or routine such as pregnancy, older age, and travel
  • Abuse of laxatives
  • Ignoring the urge to have a bowel movement
  • Specific diseases such as multiple sclerosis and lupus
  • Problems with the colon and rectum
  • Problems with intestinal function (Chronic idiopathic constipation).

Diet

The most common cause of constipation is a diet low in fiber found in vegetables, fruits, and whole grains and high in fats found in cheese, eggs, and meats. People who eat plenty of high-fiber foods are less likely to become constipated.

Fiber–soluble and insoluble–is the part of fruits, vegetables, and grains that the body cannot digest. Soluble fiber dissolves easily in water and takes on a soft, gel-like texture in the intestines. Insoluble fiber passes almost unchanged through the intestines. The bulk and soft texture of fiber help prevent hard, dry stools that are difficult to pass.

On average, Americans eat about 5 to 20 grams of fiber daily, short of the 20 to 35 grams recommended by the American Dietetic Association. Both children and adults eat too many refined and processed foods in which the natural fiber is removed.
A low-fiber diet also plays a key role in constipation among older adults. They often lack interest in eating and may choose fast foods low in fiber. In addition, loss of teeth may force older people to eat soft foods that are processed and low in fiber.

Not Enough Liquids
Liquids like water and juice add fluid to the colon and bulk to stools, making bowel movements softer and easier to pass. People who have problems with constipation should drink enough of these liquids every day, about eight 8-ounce glasses. Other liquids, like coffee and soft drinks, that contain caffeine seem to have a dehydrating effect.

Lack of Exercise
Lack of exercise can lead to constipation, although doctors do not know precisely why. For example, constipation often occurs after an accident or during an illness when one must stay in bed and cannot exercise.

Medications
Pain medications (especially narcotics), antacids that contain aluminum, antispasmodics, antidepressants, iron supplements, diuretics, and anticonvulsants for epilepsy can slow passage of bowel movements.

Irritable Bowel Syndrome (IBS)
Some people with IBS, also known as spastic colon, have spasms in the colon that affect bowel movements. Constipation and diarrhea often alternate, and abdominal cramping, gassiness, and bloating are other common complaints. Although IBS can produce lifelong symptoms, it is not a life-threatening condition. It often worsens with stress, but there is no specific cause or anything unusual that the doctor can see in the colon.

Changes in Life or Routine
During pregnancy, women may be constipated because of hormonal changes or because the heavy uterus compresses the intestine. Aging may also affect bowel regularity because a slower metabolism results in less intestinal activity and muscle tone. In addition, people often become constipated when traveling because their normal diet and daily routines are disrupted.

Abuse of Laxatives
Myths about constipation have led to a serious abuse of laxatives. This is common among older adults who are preoccupied with having a daily bowel movement.

Laxatives usually are not necessary and can be habit-forming. The colon begins to rely on laxatives to bring on bowel movements. Over time, laxatives can damage nerve cells in the colon and interfere with the colon’s natural ability to contract. For the same reason, regular use of enemas can also lead to a loss of normal bowel function.

Ignoring the Urge to Have a Bowel Movement
People who ignore the urge to have a bowel movement may eventually stop feeling the urge, which can lead to constipation. Some people delay having a bowel movement because they do not want to use toilets outside the home. Others ignore the urge because of emotional stress or because they are too busy. Children may postpone having a bowel movement because of stressful toilet training or because they do not want to interrupt their play.

Specific Diseases
Diseases that cause constipation include neurological disorders, metabolic and endocrine disorders, and systemic conditions that affect organ systems. These disorders can slow the movement of stool through the colon, rectum, or anus. Only a doctor can identify these conditions.

What Diagnostic Tests Are Used?
Most people do not need extensive testing and can be treated with changes in diet and exercise. For example, in young people with mild symptoms, a medical history and physical examination may be all the doctor needs to suggest successful treatment. The tests the doctor performs depends on the duration and severity of the constipation, the person’s age, and whether there is blood in stools, recent changes in bowel movements, or weight loss.
Extensive testing usually is reserved for people with severe symptoms, for those with sudden changes in number and consistency of bowel movements or blood in the stool, and for older adults. Because of an increased risk of colorectal cancer in older adults, the doctor may use these tests to rule out a diagnosis of cancer.

How Is Constipation Treated?
Although treatment depends on the cause, severity, and duration, in most cases dietary and lifestyle changes will help relieve symptoms and help prevent constipation.

Can Constipation Be Serious?
Sometimes constipation can lead to complications. These complications include hemorrhoids caused by straining to have a bowel movement or anal fissures (tears in the skin around the anus) caused when hard stool stretches the sphincter muscle.
Sometimes straining causes a small amount of intestinal lining to push out from the anal opening. This condition is known as rectal prolapse and may lead to secretion of mucus from the anus. Constipation may also cause hard stool to pack the intestine and rectum so tightly that the normal pushing action of the colon is not enough to expel the stool. This condition, called fecal impaction, occurs most often in children and older adults. You should see a physician if there is a persistent change in your bowel function or you develop any complications.

Points to Remember

  • Constipation affects almost everyone at one time or another
  • Many people think they are constipated when, in fact, their bowel movements are regular.
  • The most common causes of constipation are poor diet and lack of exercise.
  • Additional causes of constipation include medications, irritable bowel syndrome, abuse of laxatives, and specific diseases. 
  • A medical history and physical examination may be the only diagnostic tests needed before the doctor suggests treatment.

In most cases, following these simple tips will help relieve symptoms and prevent recurrence of constipation:

  • Eat a well-balanced, high-fiber diet that includes beans, bran, whole grains, fresh fruits, and vegetables.
  • Drink plenty of liquids.
  • Exercise regularly.
  • Set aside time after breakfast or dinner for undisturbed visits to the toilet.
  • Do not ignore the urge to have a bowel movement.
  • Understand that normal bowel habits vary.
  • Whenever a significant or prolonged change in bowel habits occurs, check with a doctor.

Most people with mild constipation do not need laxatives. However, doctors may recommend laxatives for a limited time for people with chronic constipation.