What is Egestión? Definition, characteristics and phases

This physiological process allows us to eliminate undigested materials.

Eggestion is a physiological process in which undigested materials are expelled in the form of feces. in the form of feces.

In unicellular organisms, such as bacteria, it basically consists of the expulsion of unusable materials to the outside of the cell. In contrast, in the case of multicellular organisms, such as humans, the food undergoes a longer process.

Many people confuse excretion with egestion and, although both are related to digestion, they are two different physiological processes.

Human digestion: definition and phases of this physiological process

Before going into more detail with the concept of egestion, it is necessary to understand how digestion occurs, it is necessary to understand how human digestion occurs and the processes that occur to food before it is eliminated as feces..

When we eat, food enters the digestive tract. The main function of this apparatus is to process food in order to obtain from it as many nutrients as possible and to eliminate what is not usable or has been left as waste.

A whole set of organs are involved in the digestion process: mouth, salivary glands, esophagus, stomach, pancreas, liver, gall bladder, small and large intestines, appendix, rectum and anus.

The first place where food passes through is the mouth. There it is chewed and mixed with saliva, starting digestion and beginning its decomposition. In this phase of digestion the food is called the alimentary bolus.

The food bolus goes to the stomach through the esophagus and then reaches the small intestine, where further digestion takes place. As the food has been digested, the molecules that were present in it can be absorbed more easily.

These nutrients are introduced into the bloodstream, through which they will travel to all parts of the body where they are needed.

Not everything is absorbed in the small intestine. Only the smallest and most soluble substances can be absorbed through the walls of this organ. Those that are not, which are larger and insoluble, if they have not been reduced in size by the action of enzymes, cannot be utilized.. This is the phase before egestion takes place.

What is egestion?

The part of the food that could not be absorbed in the small intestine passes to the large intestine. There, the excess water is absorbed and the remaining food is degraded by the action of bacteria..

The result of this is feces, composed mostly of water and bacteria, as well as substances that the human body cannot digest, such as cellulose and fiber. In addition to what has not been utilized, the feces contain substances that could be harmful to the body and need to be eliminated.

Bacteria in the digestive system play a very important role for humans, since they digest substances, such as certain types of carbohydrates, and synthesize proteins, such as B and K. They also fight other bacteria that could be harmful to the human body, which cause diseases and digestive problems.

Properly speaking, the process of digestion occurs when what has not been utilized by the body is stored in the rectum.. It is there that, when the signal is given, the waste is evacuated through the anus.

The output of feces is controlled by the anal sphincter, which is made up of two parts: internal sphincter and external sphincter. If there is debris in the rectum, the anal sphincter stretches and allows the stool to pass.

Differences between egestion and excretion

Today, both in general culture and in some school textbooks, these two terms are still confused. Although both are two phases present in digestion, they present certain nuances that differentiate them.

Egestion is the elimination of what came with the food and could not be used, such as non-digestible substances and elements that are harmful to the human body. for the human body. Basically, it is the part of the food that has not been introduced into the bloodstream and used by the body, and is eliminated in the form of feces.

On the other hand, excretion is a process in which substances that have been used to maintain vital functions are eliminated.. Cells need energy to carry out their functions, and for this they need nutrients. These nutrients come in the form of organic molecules, which are broken down inside the cell and produce energy. The residues of this process leave the cell and are eliminated in the urine.

Associated problems

Either by some disease or by a bad diet, there may be problems with the elimination of feces..

These problems may not be serious and may be solved with the passage of time, however, if they persist, it is necessary to see a professional to make sure that it is not the consequence of a bigger problem.

1. Diarrhea

Diarrhea occurs when watery and soft stools are eliminated, due to a short passage through the small intestine.

It can be caused by contamination in food and water, viruses, parasites, consumption and abuse of medications, food intolerance and sensitivity, stomach surgeries, stomach diseases and problems in the functioning of the colon.

2. Fecal incontinence

Fecal incontinence is the inability to control when to defecate.. It can be the result of a loss of control of the sphincters or bowels, for which it is necessary to go to a professional to help learn how to control them again.

3. Constipation

It is difficult to eliminate the feces, being able to be dry and very hard.. Although being constipated does not mean not being able to have a bowel movement every day, it is considered constipation to do it less than 3 times a week.

4. Encopresis

Encopresis is the involuntary elimination of stool in inopportune places and at inopportune times. This elimination disorder usually occurs in children from 4 years of age and can have multiple causes. It usually occurs when retained stool accumulates in the rectum and colon, producing bloating in the belly, loss of control of bowel movements and even loss of appetite.

The child cannot control the passage of stool, which may be both liquid and solid, or large enough to block the toilet.

If the child has not previously learned to control the sphincters, it is called primary encopresis. If, on the other hand, the child learned to control the sphincters before suffering encopresis, we speak of secondary encopresis. There may be emotional factors behind the child's encopresis, such as poor family dynamics.

Bibliographic references:

• Keeton, W., and Harvey, D. (2016). Human digestive system. Encyclopedia Britannica.
• Pocock, Gillian, (2006). Human Physiology (Third ed.). Oxford University Press.