It may not be a pleasant subject to discuss, but bowel regularity plays a
crucial role in your overall health.

How frequently people have bowel movements varies widely, but doctors
consider anything from three bowel movements a day, to three a week,

to be normal. That means that one person’s “normal” could mean constipation for someone
else.

Regardless of how often you normally have bowel movements, having them
regularly is important. If you don’t have one for many days, digestive waste
can back up in your intestines and eventually harm your organs.

Prolonged diarrhea, on the other hand, can cause

dehydration. That can be serious for children, older adults, and people with weakened
immune systems.

Bowel mechanics

Bowel movements are the end product of

digestion, the process through which your body breaks down food into nutrients it can
use, and gets rid of the waste it can’t.

Your small bowel (or

small intestine) breaks down the partially digested food that comes from your stomach into
liquid, and absorbs most of its nutrients. That leaves a liquid waste that
travels into your large bowel (or

large intestine), which breaks it down, absorbs water from it, shapes it into stool, and
moves it into your rectum.

Your bowels keep your digestive process flowing by contracting. How
frequently they contract determines how often you have bowel movements.

• When your bowels contract too frequently, your
large bowel doesn’t have enough time to absorb water from the liquid waste
it receives from your small bowel. It also doesn’t have time to shape the
waste. The result is the loose, watery stool associated with

diarrhea.

• When your bowels don’t contract frequently enough,
the liquid waste from your small bowel moves through your large bowel too
slowly. That results in your large bowel absorbing more water from the waste
than normal. When that happens, you pass the

hard, dry stools

associated with

constipation.

Causes of irregularity

Conditions that can cause

constipation

include:

• Intestinal blockage
• Neurological problems, such as Parkinson’s disease and multiple sclerosis
• Pelvic floor dysfunction

Dietary causes

of constipation include not eating enough fiber or not drinking enough
water, as well as eating too much sugar and animal fat. Constipation also
can be caused by some medicines, including laxatives if you rely on them too
often. Not getting enough exercise, and not relieving yourself when you have
to go, can also lead to constipation.

Common causes of diarrhea

include:

• Digestive disorders, such as irritable bowel syndrome, Crohn’s disease, and
celiac disease.
• Viruses and bacteria
• Parasites
• Food intolerances, such as lactose intolerance
• Medicines
• Heavy alcohol use
• Specific sugars, such as fructose
• Too much coffee

Constipation and diarrhea can sometimes be the result of a serious medical
condition. If you have prolonged or recurring bouts of either, you should
see a medical professional.