Digestive process in the stomach

After the human body ingests food, it will be digested in the stomach, so if you have symptoms such as indigestion and constipation, it is usually a problem with the stomach. Gastric diseases are also very harmful to human health, causing people to experience loss of appetite, stomach pain, bloating and other phenomena. This requires us to have a certain understanding of the stomach's digestive process. So, what exactly is the digestion process in the stomach?

The process of food digestion in the human body:

Food enters the human body through the mouth, then passes through the esophagus into the stomach, then enters the intestines, passes through the small intestine, large intestine, rectum, and finally is excreted from the body through the anus.

The mouth mainly chews and grinds food and moistens it with saliva to facilitate swallowing. Only a small amount of starch is broken down into maltose under the action of salivary amylase.

Gastric juice is highly acidic, which can activate proteases and promote the secretion of pancreatic hormone after entering the small intestine, thereby promoting the secretion of pancreatic juice, bile and small intestinal juice. Digestion in the stomach mainly involves the degradation of some proteins.

The small intestine is the most important stage of the digestive process. Pancreatic juice is alkaline and can neutralize gastric juice. It contains pancreatic amylase, pancreatic lipase, trypsin, chymotrypsin, nucleotidase and deoxyribonuclease, etc. It is the most important of all digestive juices. Bile promotes the emulsification and breakdown of fat. Intestinal fluid can promote the digestion of protein.

The large intestine basically does not participate in digestion. Its main function is to provide temporary storage for digested food residues. Large intestinal fluid mainly protects the intestinal mucosa and lubricates feces.

The process of food absorption in the human body:

Food is not absorbed in the mouth and esophagus. Although the mouth can degrade some starch, it cannot directly absorb the maltose after the decomposition.

Even the stomach absorbs very little food. It is a common misunderstanding that people think of the stomach when they talk about digestion and absorption. The stomach only absorbs alcohol and a small amount of water.

The small intestine is the main organ for food digestion and absorption. The carbohydrates, fats, proteins, vitamins, etc. after food digestion are all absorbed in the small intestine.

The large intestine mainly absorbs water and salts.

Water, inorganic salts and vitamins can be directly absorbed by the small intestine without digestion.

Carbohydrates can generally be absorbed by the small intestine only after being digested into monosaccharides.

After protein is digested and broken down into amino acids, almost all of it is absorbed by the small intestine.

Fatty acids, monoglycerides and cholesterol formed after fat digestion need to combine with bile salts to form water-soluble complexes before they can be absorbed by the small intestine.

Additional information:

Human digestion can be divided into two forms: mechanical and chemical.

Mechanical digestion is mainly achieved through the smooth muscles of the mouth, stomach, intestines, etc., which provide power for food from entering the mouth to final excretion through chewing, swallowing, peristalsis, etc.

Chemical digestion uses various digestive juices to degrade food, gradually digesting food from its original state into small molecules that can be absorbed by the human body.