MedFriendly®
 
 
 
Feces
Feces is a fancy way to describe something that is not
so fancy. To put it plainly, feces is poop, the matter that
is discharged from the bowels and hopefully into a
diaper or toilet bowl. You may have also heard to it
referred to as crap or stool (see the entry on stool
softeners). Feces are a waste product or substance
that is excreted from the digestive tract. Feces are
formed in the digestive tract and sent out through the
rectum (rear end).
Coliform bacteria from feces under the
microscope.
 
FEATURED BOOK: What's Your Poo Telling You?

WHAT ARE FECES MADE OF?

If you have ever wondered what feces are made of, you have come to the right place.
Feces are mostly made of water (about 75%). The rest is made of dead bacteria that
helped us digest our food, living bacteria, protein, undigested food residue (known as
fiber), waste material from food, cellular linings, fats, salts, and substances released from
the intestines (such as mucus) and the liver.

Although feces are made up of about 75% water, this number varies from person to
person, depending on how long the feces stay in the intestine. Since the intestines
absorb water from the feces, diarrhea (poop that passes quickly through the intestines)
will contain more water and retained feces (which stay in the intestines for a longer
amount of time) will contain less. Another point worth mentioning is that fiber helps feces
pass along the intestine.
"Where Medical Information is Easy to Understand"™
HOW OFTEN DOES THE AVERAGE PERSON POOP?

The best way to answer this question is with a normal range, since
there is variation from person to person. The normal range for daily
pooping is from three times a day to once every three days.
Therefore, it would be fair to say that the average person poops
about once a day. When someone poops four times a day or more
and the poop has a liquid consistency, this is referred to as
diarrhea. When someone poops less than two or three days a week
and the poop is hard, dry, and difficult to pass, this is known as
constipation.
WHAT DO THE BACTERIA INSIDE OF FECES LOOK LIKE?

The bacteria inside of feces can take many different shapes and appearances. Above is a picture of a
common type of bacteria found in feces known as fecal coliform bacteria (fecal means pertaining to
feces).

WHAT MAKES FECES SMELL SO BAD?

The bacteria inside of the feces is what makes them smell so bad. Specifically, the bacteria produce
various compounds and gases that lead to the infamous smell of feces. Just in case you were wondering,
you can get very sick by eating feces because it contains so many types of bacteria and other harmful
substances such as parasites. So we wouldn't suggest adding feces to your diet any time soon.

CAN I REDUCE THE BAD SMELL OF MY FECES?

Yes. Feces will vary in smell depending on the type of foods and drinks that you consume. Generally
speaking, feces will smell worse if you consume foods or liquids with many artificial flavors or chemicals in
them. The bad smell of feces will usually be reduced by eating more natural foods that do not contain any
artificial flavors or chemicals. Remember, however, that these are general guidelines that vary from
person. The only way to know for sure is to monitor the smell of feces depending on the types of foods in
the diet and to see if the smell changes when certain foods are removed or added.

WHY ARE FECES BROWNISH-YELLOW IN COLOR?

Feces are mostly shades of brown or yellow because they are also made up of an orange-yellow
substance called bilirubin that is present throughout the body and particularly in the intestine. When iron
combines with bilirubin, it gives it a brown color. The iron-influenced bilirubin then combines with the feces
and turns it brown.

WHAT CAUSES FECES TO BE MOSTLY YELLOW?

One condition that can cause yellow poop is an infection known as giardia. Giardia are tiny organisms
that are also parasites. Parasites are organisms that live in or on another organism to obtain nourishment.
If giardia infects the intestines it can cause severe yellow diarrhea. This is a dangerous infection that can
spread to others. In fact doctors that see it have to report it to the government's Center for Disease
Control and Prevention.

Another cause of yellow poop is a condition known as Gilbert's syndrome. This condition is characterized
by jaundice (a yellow discoloration of the skin) and hyperbilirubinemia. Hyperbilirubinemia is when too
much of a substance known as bilirubin (a red pigment secreted by the liver) is present in the circulating
blood. Since bilirubin is an orange-yellow color, too much bilrubin in the blood can lead to yellow-colored
skin and yellow poop. See your doctor if you are concerned about the color of your poop.

WHAT OTHER COLORS CAN FECES BE?

Feces can be black if dried blood is present in it from a bleed. More active bleeding can lead feces to be
red. In addition, intense red food coloring can cause bright red poop. Sometimes brightly colored foods
pass through the body almost unchanged, and the poop may be speckled with bright red spots. Even more
strange is that feces can be blue or green in children with certain illnesses or if they eat food with a lot of
green or blue food coloring. Babies can also get green feces when they are given food for the first time.

Adults can also have green poop if they eat large amounts of green, leafy vegetables or if they eat large
amounts of foods with green food coloring. Green feces can also occur with diarrhea if bile salts pass
through the intestine unchanged. Bile salts are substances that make up bile, which is a fluid produced by
the liver that help digest fat. The liver is the largest organ in the body and is responsible for filtering
(removing) harmful chemical substances, producing important chemicals for the body, and other important
functions.

Feces can even appear white if one drinks a substance known as barium sulfate. Barium sulfate is often
given to patients getting an X-ray of the digestive tract because it assists doctors in visualizing the
resulting picture from the X-ray better. See your doctor if you are concerned about the color of your poop.

HOW ARE FECES EXAMINED TO DIAGNOSE MEDICAL PROBLEMS?

To diagnose various medical problems, feces are often examined for their smell, color, quantity, and
consistency. Feces are also examined under a microscope for blood, mucus, fat, or parasites (organisms
that live on or in another organism and gain nourishment from it).

WHAT DOES IT MEAN IF THERE IS UNDIGESTED FOOD IN THE FECES?

If food appears in the feces looking very similar to how you it was when you ate it, this means that the
food has not been digested (broken down and absorbed) by the body. Believe it or not, many foods that
we eat cannot be digested by the enzymes in our digestive system. An enzyme is a type of protein that
helps produce chemical reactions in the body.

Foods that cannot be digested by the human body usually contain a high amount of dietary fiber. Dietary
fiber is a term for chemical substances in the cells of plants that cannot be digested by the human body.
Dietary fiber cannot be digested by the human body because it lacks the necessary enzymes to do so.
More specifically, dietary fiber is resistant to hydrolysis. Hydrolysis is a process in which a substance is
broken down by splitting its chemical bond and adding water to it. Since dietary fiber cannot be digested, it
passes through the body virtually unchanged and cannot be used as an energy source. Although humans
cannot digest dietary fiber, some of it is broken down by bacteria to produce gas and acids.

Examples of foods that are not digested well by the human body include corn, peanuts, peas, carrots,
cereals, and beans. If the bacteria in the body are successful, some of the carbohydrates in these foods
may be broken down. If not, however, we will see these foods in the feces. Carbohydrates are a group of
substances present in certain types of foods (such as sugar) that provides the body with energy.

Research also suggests that the more a food is cooked, the more difficult it is for the body to digest it.
This is generally true of most foods. The higher the temperature that the food is cooked, the longer it will
stay in the digestive system, and the more difficult it will be for the body to digest. Why does this happen?
To begin with, all foods are made up of chemicals that are arranged in certain patterns. Our digestive
system is generally able to break down foods that fit these general patterns. However, the chemical
patterns of all foods can be changed when they are heated past a certain point. Thus, foods that are
deep-fried and barbecued often have their chemical pattern changed. As a result, the body does not
understand how to deal with these new chemical patterns and the food can pass out of the body
undigested because the body does not have the necessary enzymes to digest it properly.
If the above reasons are not causing food to be undigested, this could indicate a problem in the digestive
system. In a healthy person, it should take between 24 and 36 hours to digest food. If the food comes out
of the body faster than this, this usually means that there is a build up of debris (the remains of something
broken down) that is preventing the colon from digesting food.

The colon is the major part of the large intestine, that absorbs water and some types of salts from the
digested material that passes through it. The intestine is a tube shaped structure that is part of the
digestive tract, and is located in the belly. The large intestine absorbs moisture from the matter that is left
after it is digested in the small intestine, and releases the waste from the anus (the area that feces comes
out of). The small intestine is a part of the intestine that takes in all of the nutrients (healthy substances)
that the body needs.

A healthy piece of feces is about one foot long. Shorter sized feces suggest that the colon is not able to
process the food correctly and that the feces produced does not have the correct amount of moisture in it.

WHAT IS A FECALOMA?

A fecaloma is a a buildup of thickened, stone-like feces. Click the fecaloma link to learn more.

WHAT ELSE ARE FECES CALLED?

Feces are also known as stool and stercus. The word fecaloid means resembling feces (e.g., mud).

WHY IS IT CALLED FECES?

Feces comes from the Latin word "faex," which means "dregs." Dregs means the most undesirable part.