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. Also, 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 its causes, prevention, and treatment will help most
people find relief.
Who gets constipated?
According to the 1996 National Health Interview Survey, about 3 million
people in the United States have frequent constipation. Those reporting
constipation most often are women and adults age 65 and over. Pregnant women may
have constipation, and it is a common problem following childbirth or
Constipation is one of the most common gastrointestinal complaints in the
United States, resulting in about 2 million doctor visits annually. However,
most people treat themselves without seeking medical help, as is evident from
the millions of dollars Americans spend on laxatives each year.
What causes constipation?
To understand constipation, it helps to know how the colon (large intestine)
works. As food moves through the colon, it 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 or if the colon’s muscle contractions are slow or sluggish, causing the
stool to move through the colon too slowly. Common causes of constipation
- not enough fiber in the diet
- not enough liquids
- lack of exercise
- 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 stroke (by far the most common)
- problems with the colon and rectum
- problems with intestinal function (chronic idiopathic constipation)
Not Enough Fiber in the 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
Fiber—both 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
through the intestines almost unchanged. The bulk and soft texture of fiber help
prevent hard, dry stools that are difficult to pass.
According to the National Center for Health Statistics, Americans eat an
average of 5 to 14 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 from which the natural fiber has been
A low-fiber diet also plays a key role in constipation among older adults,
who may lose interest in eating and choose convenience foods low in fiber. In
addition, difficulties with chewing or swallowing may force older people to eat
soft foods that are processed and low in fiber.
*National Center for Health Statistics. Dietary Intake of
Macronutrients, Micronutrients, and Other Dietary Constituents: United States,
1988–94. Vital and Health Statistics, Series 11, number 245. July 2002.
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. Liquids that contain caffeine, like coffee and cola drinks, and alcohol
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.
Some medications can cause constipation. They include
- pain medications (especially narcotics)
- antacids that contain aluminum and calcium
- blood pressure medications (calcium channel blockers)
- antiparkinson drugs
- iron supplements
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 people 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.
Diseases that cause constipation include neurological disorders, meta