Physiological functions of the stomach

Everyone has a stomach in their body. The stomach not only helps us store food, but also provides us with energy through digestion. The stomach is very important to us. If our stomach is damaged, we will feel stomach pain, and we may also have some indigestion, constipation or diarrhea. So what are the physiological functions of the stomach?

The stomach is located below the diaphragm, connected to the esophagus above and the small intestine below. The stomach and spleen are located in the middle burner and are "connected by a membrane". They are connected by the Stomach Meridian of Foot-Yangming and the Spleen Meridian of Foot-Taiyin, forming an exterior-interior relationship. The stomach and spleen both belong to the earth in the five elements: the stomach is Yangming dry earth, which is Yang; the spleen is Taiyin wet earth, which is Yin. The gastric cavity is called the gastric cavity, which is divided into three parts: upper, middle and lower. The upper part of the stomach is the upper cavity, including the cardia; the lower part of the stomach is the lower cavity, including the pylorus; the part between the upper and lower cavities is called the middle cavity. The cardia is connected to the esophagus above and the pylorus is connected to the small intestine below, forming the passage for food to enter and exit the stomach. The main physiological function of the stomach is to receive and digest food. The physiological characteristics of the stomach are that it promotes downward movement and likes moisture and dislikes dryness.

( I) Main physiological functions

It is responsible for receiving and digesting food and water. The stomach is responsible for receiving food and water, which means that the stomach qi has the function of accepting and accommodating food and water. Food enters the mouth through the esophagus (pharynx) and enters the stomach. Under the action of the gastric qi, the stomach receives and contains it, so the stomach is known as the "Taicang" and the "sea of ​​water and grain." After being ground and fermented by the stomach qi, the food forms chyme and is initially digested. The fine substances in the food in the stomach are absorbed and transferred by the spleen qi (dependent on the spleen qi) to nourish the whole body. The undigested chyme is transmitted to the small intestine for further digestion. The production of the body's essence, qi, blood, and body fluids all depend on the nutrients in food, so the stomach is also known as the "sea of ​​water, grain, qi, and blood." Traditional Chinese medicine attaches great importance to the role of "stomach qi". Stomach Qi is both the physiological function of the stomach and the physiological function of the spleen and stomach. As the "acquired foundation" of all nutrition sources, it is very important for human life activities. Hence there is a saying that “if there is stomach qi, there is life, and if there is no stomach qi, there is death.”

(II) Physiological characteristics

1. The stomach is responsible for the downward flow and downward flow, which means that the stomach Qi should maintain an unobstructed and downward movement trend. The descending and promoting function of stomach qi is mainly reflected in the process of food digestion and waste excretion: ① Food enters the stomach, and the stomach accommodates it without rejecting it. ② The chyme formed by the fermentation of stomach qi is transmitted to the small intestine for further digestion. ③Food residues move down to the large intestine and form feces after drying. ④Feces is discharged from the body in moderation. The Zang-Fu theory summarizes the physiological functions of the entire digestive system through the rising and falling movements of the spleen and stomach qi. The spleen is healthy when it rises, and the stomach is harmonious when it descends. The spleen rises and the stomach descends in coordination, which together promotes the digestion and absorption of food.

The stomach's main function is to descend turbidity, and descending turbidity is a prerequisite for receiving food. Therefore, if the stomach fails to function properly, symptoms such as poor appetite, abdominal distension or pain, and constipation will occur. If the stomach qi does not descend but instead rises upward, symptoms of stomach qi rising upward, such as nausea, vomiting, hiccups, and belching, will occur. The spleen and stomach are located in the center and are the hub for the rise and fall of Qi in the human body. The descending of stomach qi and the ascending of spleen qi complement each other, and the disharmony of stomach and the failure of spleen qi to ascend can also affect each other. When the stomach fails to coordinate and descend, it not only affects the descending of the six bowels, but also affects the rise and fall of Qi throughout the body, resulting in various pathological changes. For example, in Suwen·Ni Tiao Lun, it is said that “if the stomach is not in harmony, one will not be able to sleep well.”

2. The stomach likes moisture and hates dryness. The stomach likes moisture and hates dryness, which means that the stomach should maintain sufficient body fluid to facilitate the reception and digestion of food. The stomach's reception and digestion of food not only depends on the propulsion and evaporation of stomach qi, but also requires the lubrication of body fluid in the stomach. If there is sufficient fluid in the stomach, it can maintain its function of receiving and digesting food and its characteristic of promoting circulation and descending. The stomach is Yang Earth, which likes moisture and hates dryness, so diseases of the stomach are easily caused by dryness and heat, and the body fluids in the stomach are often damaged. Therefore, when treating stomach problems, pay attention to protecting the body fluid in the stomach. Even if bitter and cold purgatives must be used, their use should be stopped as soon as the disease is cured, with the goal of eliminating the excess heat and dryness. Do not use them recklessly to avoid causing dryness and damaging the yin.