The human digestive system is made up of several organs, among which the stomach stands out, which is located in the upper part of the abdomen, right between two other organs; the esophagus and duodenum. On the other hand, it can be considered the most important organ of the digestive system, since its function is very important, because it is responsible for storing food, digesting food, mixing what is consumed with gastric acids and also, it is also responsible for removing the nutrients, vitamins and minerals found in food (and in general, everything consumed.
The stomach is defined as the portion of the digestive tract that is located between the esophagus and the intestine. It is located in the abdomen, just in the upper left region, below the diaphragm. In the stomach, food is stored and mixed until it is discarded with the help of gastric emptying, which is responsible once the stomach is full, sending waste to the duodenum.
Index
What is the function of the stomach?
The food that is ingested reaches the stomach and is processed thanks to the gastric juices, in order to reach the small intestine and continue with the digestion process.
The time that food can take from the stomach to the small intestine, will depend on different factors, such as; if it is solid or liquid food, if it is composed of fats, carbohydrates or proteins. It finally gives the signals that digestive hormones produce or it depends on how full you can be.
When the stomach is empty, a liquid such as water can take approximately 10 to 20 minutes to pass into the stomach. In the case of solid foods, they only pass into the intestine once they are sufficiently crushed, with particles smaller than 2 millimeters, spending at least six hours in the stomach.
What are gastric juices
Once in the stomach, the food is transformed into a paste with a pasty texture known as chyme or food bolus. This is accomplished with the help of gastric juices, a mixture of secretions from various surface cells and gastric glands. The chemical composition of these juices is made up of water, traces of potassium chloride, hydrochloric acid, sodium chloride, enzymes, bicarbonate and mucus.
Stomach physiology
The stomach fulfills various functions that are essential for the human being, especially in relation to food processes, among these functions are:
- Perform partial digestion of proteins thanks to pepsin, continuing in the small intestine.
- Depositing food, the stomach has a capacity of one thousand to two thousand cubic centimeters of bactericidal action.
- Stimulates the secretions of bile and pancreatic juice.
- Produces alkaline mucus, to protect the mucous membranes.
- Adsorbs water.
- It produces intrinsic factor, a substance that absorbs vitamin B12.
Stomach anatomy
The size of the stomach is approximately 25 cm in length transverse and 8 cm in length anteposterior. It also has a capacity of 1000 to 1500 cubic centimeters. It is located in the upper left part of the abdomen, occupying part of the epigastrium, umbilical region and left hypochondrium.
It should be noted that both the shape, position, size and dimension vary according to sex, age, muscle tone, posture and physiological moment. The shape of the stomach resembles a J, it has two faces: the anterior and the posterior, which have two curvatures, major and minor. It also has two orifices: the upper one called the cardia and the lower one known as the pyloric portion.
Parts of the stomach and their functions
The position of the stomach can vary depending on whether the person is standing or lying down and can be divided into different parts:
- Cardias: hole that connects the stomach with the esophagus. It has muscle fibers that prevent gastric acid content from flowing back into the esophagus.
- Fundus: upper part of the stomach, closer to the cardia.
- Body: central or main part that makes up the stomach.
- Antrum: lower region found in the stomach, close to the pylorus.
- Pylorus: one of the parts between the stomach and duodenum. It is responsible for thickening the muscle fibers of the wall of the digestive tract, which is responsible for converting the sphincters and thus control gastric emptying.
Stomach walls
The stomach walls are made up of five layers, which are divided as follows:
- Inner layer, known as the mucosa that produces gastric juices and digestive enzymes.
- Supporting layer or submucosa.
- Its own muscular layer, which is responsible for moving the muscle and mixing the contents of the stomach.
- Two outer layers, known as the subserosa and serous, that act as the lining of the stomach.
Stomach diseases
The stomach can be sensitive to different ailments and diseases that can interrupt the normal functioning of this organ, among the most common are.
Indigestion
It is one of the most common stomach problems, which produces sensations of heat, burning or pain in the area of the navel or the lower part of the breastbone. In the same way, it produces a feeling of satiety that is annoying, which begins just after finishing the meal.
The trigger for indigestion can occur from consuming alcohol, overeating, having stress, gallstones, or taking a drug. Usually this discomfort can be alleviated by medications such as antacids, which are available over the counter.
Heartburn
Being another of the most common stomach problems, heartburn is characterized by causing pain in the chest or throat. This occurs because acid from the stomach backs up into the esophagus, creating a burning sensation that travels up to the larynx. People who have these symptoms more than twice a week may have GERD problems.
The causes of heartburn are associated with pregnancy, alcoholic beverages, cigarettes, excess caffeine, some foods and even medicines. Treating this condition is important as it could eventually damage the esophagus.
Stomach cancer
Stomach cancer begins to develop slowly, normally certain precancerous changes begin to occur in the inner lining of the stomach. Since these changes do not produce any symptoms, it is very difficult to detect them early.
Each type of cancer produces different symptoms and therefore have different consequences. In addition, depending on the location, it can affect the treatment options. Among the different types of stomach cancer, are.
Adenocarcinoma
It is the most common type of gastric cancer up to 95%, an adenocarcinoma originates in the cells that are responsible for forming the innermost layer of the stomach, known as the mucosa.
Lymphoma
It refers to those cancerous tumors that form in the immune system and begin to be detected in the walls of the stomach. The treatment given to this type of cancer will depend on the type, which is usually related to non-Hodgkin lymphoma .
Gastrointestinal stromal tumors (GIST)
Although rare, gastrointestinal stromal tumors originate in cells in the stomach wall, which are known as interstitial cells of Cajal. Some of the tumors may not be cancerous.
It should be noted that although many gastrointestinal stromal tumors are found anywhere in the digestive system, most of them are discovered in the stomach.
Other types of cancer
There are other types of cancer such as carcinoid tumors (that do not spread to other organs), small cell carcinoma, squamous cell carcinoma and leiomyosarcoma, although these are cancers that occur less frequently.
Stomach care
As it is the organ that processes all the food that is eaten, it is necessary to take certain care to avoid any type of illness or discomfort. Some of the care that should be taken into account to maintain good stomach health are the following:
- Limit the consumption of foods that are irritating such as alcohol or spicy.
- Review the type of medications to be ingested and if they have any adverse reactions in the stomach.
- Avoid eating spoiled food.
- Chew food well, since eating quickly prevents proper digestion.
- Eat moderate portions, avoiding overeating.
- Drink plenty of purified water.
- Avoid street food.
- Eat foods rich in fiber.
conclusion
The stomach fulfills one of the most important functions in the body, digesting the food that is eaten daily. That is why it is necessary to maintain proper care of this organ and go immediately to a specialist if frequent discomfort is noticed, in order to avoid any future damage.
Dr. Samantha Robson ( CRN: 0510146-5) is a nutritionist and website content reviewer related to her area of expertise. With a postgraduate degree in Nutrition from The University of Arizona, she is a specialist in Sports Nutrition from Oxford University and is also a member of the International Society of Sports Nutrition.