How Food Becomes Nutrients

When food is solid, we chew it. We swallow it if it is liquid. Then it goes down our throats. It is interesting to know what happens to food throughout the digestive tract and how our eating habits influence our health, fitness and well-being.

Mouth process:

When we chew our food in our mouths, it breaks into small pieces and mixes with saliva. Saliva is a colorless watery liquid that is always present in our mouth. It contains enzymes that digest food. These enzymes in saliva convert insoluble starches into water-soluble substances.

This is actually the process of digestion. Enzymes convert many complex food substances into simpler substances that can then be absorbed by the body and used for its needs. These enzymes are produced by different organs / glands. What is ultimately left after food processing in the digestive tract is of no use to the body and is disposed of as feces or feces.

When we smell food, our mouths water. Saliva begins to flow down from all three pairs of salivary glands: one pair below and in front of each ear, another pair at the back of the lower jaw, and the third pair under the tongue.

We normally produce 8-10 cups of saliva a day in our mouth.

The enzyme in this saliva breaks down carbohydrates into simpler soluble forms of sugar.

The more we break food by chewing, the better. Saliva can act faster on food. Chewing well helps the digestion process. (Each bite of food is said to be chewed 32 times, once for each tooth.)

Then the food passes down our throat through the esophagus. The small flexible lid of our food pipe, called the epiglottis, closes automatically when we swallow our food. It prevents the food from going through the wrong passage which is the trachea, which is located next to it.

Stomach process:

The stomach is an important pouch-shaped organ. It constantly contracts, relaxes, and churns the food inside. The inner lining of the stomach secretes many enzymes.

These enzymes help break down proteins to allow the body to absorb nutrients. These nutrients are then used by the body for repair or growth of the body or for fuel (energy).

There are a large number of glands within the lining of the stomach. One of the enzymes, called renin, converts milk protein into soft curds. Another enzyme, called pepsin, breaks down long protein chains into smaller units called peptones that are soluble in water.

The stomach also produces a large amount of hydrochloric acid. This is the same acid that we see in the chemical laboratory. This acid does many jobs as follows:

1) It weakens proteins by loosening some of their bonds.
2) Dissolves minerals from various foods we eat.
3) It kills bacteria that enter our stomach with the food we eat.

Food stays in the mouth for a few minutes, but stays in the stomach for hours. peak secretion of renin, pepsin, and hydrochloric acid occurs approximately two hours after eating a meal. The digestion of food at this time continues very actively.

Digestion in the stomach basically consists of breaking down proteins into simpler peptone units with the help of two enzymes and hydrochloric acid.

The stomach outlet valve, which remains closed most of the time during the day, opens occasionally and allows a very small amount of semi-digested / digested food to continue into the small intestine. This valve opens and closes automatically. Allows partially digested pasty and semi-fluid foods to pass into the small intestine.

Small intestine process:

The small intestine is a long tube that further processes semi-digested food that comes from the stomach.

The upper part of the small intestine is called the duodenum and is about 25 cm long. There are three main juices that digest food in the small intestine. Juice of bile, a bitter substance that comes from the liver.

The second comes from the pancreas and the third from the small intestine. The juice of the small intestine leaks from many places along the way. The small intestine is quite long, about 5 to 6 times as long as its own height. It is properly bent 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 break down peptones (derived from proteins) into individual amino acids.

Pancreatic juice also digests both fat and carbohydrates. Carbohydrates are converted to soluble glucose by pancreatic juice. Similarly, lactose (present in milk) is also converted to soluble glucose.

Fats are digested into simpler substances with the help of another type of secretion from the liver.

The liver is the chemistry laboratory of the human body.

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

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

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

The inner lining of the small intestine has several tiny, finger-like projections called villi. These are sucking organs that digest sixteen materials and transfer them to the blood.

A part of the digested fat is also carried through another network called the lymphatic system. This system also empties its contents into blood, somewhere near the neck.

Vitamins and minerals are often water soluble and are not broken down or absorbed into the blood after being separated from food when other nutrients are digested. Vitamin A, which is fat soluble, is absorbed from the small intestine in a similar way to fat itself.

The food we eat eventually reaches the bloodstream. It is then carried to all parts of the body, to supply its energy needs and body building and regulation of bodily functions.

Large intestine process:

The large intestine is located next to the small intestine and is tubular in shape. Its interior is smooth without protrusions. It is placed on the abdomen in the shape of the English letter U upside down.

As the digested food passes through the intestine, the water is absorbed through the walls and passes into the blood. Food becomes less liquid and tough. The decomposition of digested food gives rise to some substances that carry a bad smell. Undigested food is expelled from the body in the form of stool through the opening called the anus.

How is digested food useful?

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

Glucose is absorbed by the villi in the small intestine directly into the bloodstream. It travels throughout the body and is used by the muscles as a source of energy for their operation.

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

Some glucose always circulates in the blood and the level is stable. When the sugar level rises, it is a sign of a failure, like diabetes.

Fats are broken down into simpler intermediate forms, eventually into glycerol and fatty acids. Some of these fatty acids go directly to the blood and then to the liver, as does glycerol. These fatty acids are used for energy or are sent through the blood to other parts of the body. They can then be used for energy or converted back into fats, which are sent through the blood for storage as fatty tissues.

Any excess food that we eat in excess of our needs is converted and stored primarily in the form of fat. When we receive insufficient food (for example, during fasting), the fat stores are depleted first.

Proteins enter the bloodstream in the form of amino acids, which are its building blocks. In various places in the body, these amino acids are picked up by the body’s organs and incorporated into a variety of compounds.

Tissue proteins, enzymes, hormones, and many other chemical compounds are proteins in nature. The liver itself produces and stores proteins in the body.

Vitamins and minerals are also stored in the liver. Whenever the body needs them, they are released to the parts and organs of the body.

Conclution

There are thousands of interconnected processes in our body, all the time. Food is digested and then absorbed in the small intestine. All the vital nutrients absorbed then circulate through the blood to different parts / organs of the body. And the process continues.