The body requires nutrients to generate energy for use, growth, and repair of cells. The digestion of food is what the body needs to do this. Before the cells can receive nutrients, our body breaks down the food we eat into smaller molecules of carbohydrates, protein, fats, and vitamins. Here is a summary of the nutrients our bodies absorb;

CARBOHYDRATES

These are the sugars, starch, and fiber that are in many foods. Carbohydrates can be simple or complex. Whereas simple carbohydrates are sugars found naturally in foods like fruits, vegetables, milk and milk products and added sugar, complex carbohydrates include starch and fiber found in whole-grain bread, cereals, legumes, etc.

PROTEINS

Meat, eggs, and beans are large molecules of protein which the body must digest into smaller molecules called amino acids before it can be used in the blood.

FATS

Fat molecules are excellent sources of energy for the body as well as help the body to absorb vitamins. Oils from corn, olive, soybean, and sunflower are considered healthy fats while butter, and snack foods are termed less healthy fats. For the body to absorb fat and use it, it breaks it down from fat molecules into fatty acids and glycerol.

VITAMINS

Vitamins are typically classified based on the fluids they dissolve in. Hence there are water-soluble vitamins and fat-soluble vitamins. All vitamin-Bs and Cs are known as water-soluble vitamins while vitamins A, D, E, and K are fat-soluble. The body can easily store fat-soluble vitamins in the liver and fatty tissues but discards excess water-soluble vitamins in the urine.

For every food you eat, the digestion of the food starts immediately as the food moves through the gastrointestinal tract. Digestion begins in the mouth while chewing and ends in the small intestine. The food mixes with digestive juices within the track thereby breaking large molecules of food into smaller molecules. These smaller molecules are what the body absorbs through the walls of the small intestine into the bloodstream for the rest of the body. The movement of the walls of the organs of the gastrointestinal tract, called Peristalsis, is a key factor that initiates mixing of food contents to aid digestion. The organs of the gastrointestinal tract include;

ESOPHAGUS

This is a muscular tube that transports food and liquids from the mouth to the stomach. The passage and control of food and liquid between the Esophagus and the stomach is done by a ring-like muscle known as the lower esophageal sphincter. This muscle is always closed, but as food approaches, it relaxes and allows food pass through to the stomach.

STOMACH

This organ is where swallowed food and liquid is stored, mixed with digestive juice produced therein, and producing a chyme, which it empties into the small intestine. Also, a large quantity of food sent by the Esophagus can be adequately accommodated due to relaxation of the muscles of the upper part of the stomach.

SMALL INTESTINE

The muscles of this organ produce a digestive juice which it uses to mix food from the pancreas, and liver before pushing forward for further digestion. It is in the small intestine that nutrients are absorbed into the bloodstream and distributed to the rest of the body.

LARGE INTESTINE

All waste products from the digestive process as well as older cells from the track are stored in the large intestine. Any other remaining nutrient or water is absorbed from the waste before being converted to stool, which is stored in the rectum and removed from the body during a bowel movement.

Hence, it is these organs of the gastrointestinal tract that produces digestive juices that the body uses to break down nutrients for its use. These juices contain enzymes, which are substances that hasten the chemical reactions involved in the breaking down of food into nutrients.

SALIVARY GLANDS

For food to move easily from the Esophagus to the stomach, the salivary glands produce saliva which moistens food for digestion. An enzyme which begins the breakdown of starch is also contained in saliva.

STOMACH LINING GLANDS

Protein is acted upon by stomach acid produced by the stomach lining glands to aid its digestion into body nutrients.

PANCREAS

Several enzymes that break down carbohydrates, fats, and proteins are produced in the pancreas. The small intestine also receives digestive juice from the pancreas through ducts for nutrient absorption into the bloodstream.

LIVER

Bile is an important digestive juice that is produced by the liver for the digestion of fat. As bile is produced, it is stored in the gall-bladder, which squeezes bile through the bile ducts. When you eat fatty food, the bile mixes with the food to dissolve the fat into watery contents for the small intestine. Without the bile juice, our body cannot break down fat molecules into nutrients.

SMALL INTESTINE

The final break down of proteins and starch produces glucose molecules that the body can absorb. This is aided by the combination of pancreatic juice, bile and other digestive juice produced in the small intestine. Enzymes that digest carbohydrate further are also produced by some bacteria found in the small intestine.

IN CONCLUSION

Our body cannot work efficiently if the foods we eat are not broken down into nutrients. It is until digestion is complete that specialized cells carry these nutrients through the bloodstream to different parts of the body. The liver, for example, can now work efficiently with simple sugars, amino acids, glycerol, and vitamins and salt it receives from the bloodstream.