Process of Food Digestion - An Interesting Story

in Food

We chew our food when it is solid. We swallow it if it is liquid. Then it goes down our throats. It is interesting to learn what happens to food in entire digestive track and how our food habits influence our health,fitness and wellness.

Mouth process:

When we chew our food in mouth it gets broken into small pieces and gets mixed with saliva. Saliva is a liquid which is always present in our mouth. These enzymes convert insoluble starches in soluble substances.

Actually this is the process of digestion. Enzyme converts many complex food substances into simpler substances which then can be digested by body and used for its needs. These enzymes are made by different organs / glands. What finally remains after processing of the food which is not useful for the body is thrown out as stools.

Saliva is made from salivary glands. There are three pairs of these glands in the mouth. We normally produce about 8 to 10 cups of saliva in a day in our mouth.

The more we break our food by munching, the better. Saliva can then act faster on the food. Thorough chewing helps digestion process.

Food then passes down our throat through our throat and food pipe.

Stomach process:

Stomach is an important bag shaped organ. It constantly contracts and relaxes and churns the food inside. Inside lining of stomach secretes many enzymes.

These enzymes help to breakdown proteins in order to allow body to absorb nutrients. These nutrients are then used up by body for body repair or body growth or as a fuel (energy).

Stomach also make large amount of hydrochloric acid. This is the same acid which we see in the laboratory. This acid does many jobs as follows:

1) It weakens the proteins by loosening some of their links.

2) It dissolves minerals from various foods we eat

3) It kills bacterias which enter our stomach with the food we eat.

Food stays in the mouth for a few minutes but stays in the stomach for hours. Digestion in the stomach is basically breaking down of proteins into simpler peptone units (Enzyme pepsin breaks down protein into smaller chain protein units called Peptones) with the help of enzymes and hydrochloric acid.

Outflow valve of stomach which remains closed most of the time during the day, opens up occasionally & allows very small amount of digested food to proceed further into small intestine. This valve opens and closes automatically. It allows partly digested semi-fluid, pasty food to pass through.

Small intestine process:

Small intestine is a long tube which further processes the semi-digested food which comes from stomach.

Top part of small intestine is called duodenum and is about 25 cms long. There are main three juices which digest food in the small intestines. Bile juice, a bitter substance comes from liver.

Second one comes from pancreas and third one from small intestines. Small intestine is quite long about 5 to 6 times longer than your own height.It is properly folded in the abdomen. Most of the digestion takes place in this small intestine.

The digestion process is somewhat complicated. Pancreatic juices contain many enzymes and hormones. These help breaking down of peptones into individual amino acids.

Pancreatic juice also digests fats and carbohydrates. These are converted into glucose.

The liver is the chemistry laboratory of the human body.

Blood flows from heart to liver. The liver controls the level of sugar in the blood & storage of such sugars in the muscles. It takes amino acids from the blood and makes them into proteins and stores it.

It releases these proteins when required by the body. It also destroys poisonous substances and stores vitamins and minerals.

All the food which is by now broken down into simple, mostly water soluble substances is absorbed in the body through small intestine.

Absorbed nutrients are transferred to blood. Blood carries these s nutrients through circulatory process to variety of organs.

Some part of digested fats also gets carried away through lymphatic system. This system also empties its contents in blood.

Food which we eat finally reaches blood. It is then carried to all parts of the body, to supply their needs of energy and the body building and regulation of body functions.

Large intestine process:

The large intestine is situated next to small intestine and is tubular in shape. Its inside is smooth without any projections. It is placed in abdomen in the shape of English letter U upside down.

As the digested food passes along the intestine, water is absorbed from through the walls and into the blood. The food becomes less liquid and becomes hard. The undigested food is then thrown out of the body in the form of stools through the opening called Anus.

How the digested food is made useful?

Carbohydrates (starches & sugars) are broken down first in mouth and then in the small intestine into simple sugars chiefly glucose.

Glucose is absorbed by the small intestine directly into the blood stream. It travels all over your body and is used by muscles as a source of energy for their working.

A small part of glucose is converted into glycogen which is the form in which glucose is stored both in muscles (about two thirds) and in the liver (about one third).

Some glucose is always circulating in the blood and the level is steady. When the sugar level goes up it is a sign of a fault -- the disease diabetes.

Any excess food which we eat above our requirements is converted into and stored away mostly in the form of fat. When we get insufficient food (e.g. during fasting) fat deposits are first used up.

Proteins reach blood stream as amino acids which are their building blocks. Vitamins and minerals are also stored in the liver. Whenever body needs them these are released to the body parts and organs.

March 22, 2009

Author Box
Pradeep Mahajan has 1 articles online

Author is a free-lance writer. He is an engineer-MBA and management consultant by profession & practice. Also visit for more information on health, fitness & wellness.

Add New Comment

Process of Food Digestion - An Interesting Story

Log in or Create Account to post a comment.
Security Code: Captcha Image Change Image
This article was published on 2010/04/03