The functions of the TCM Stomach

This is the most important of the Yang organs. With its paired organ the Spleen, it is responsible for the formation of post-heaven Qi from the digestion of food and drink.

The functions of the Stomach are:

• Controls ‘rotting and ripening’ of food and drink
• Controls the transportation of food essences
• Controls the descending of Qi
• Is the origin of fluids
• Effects of mental function
• Effects dreams
• Close relations with the Spleen

Controls ‘rotting and ripening’ of food and drink

The fermentation of food and drink happens in the Stomach. This makes it possible for the Spleen to transform the refined essences from the food for Qi and blood production (root of post-heaven Qi). It has always been said that if the Stomach Qi is strong, the prognosis is good.

Controls the transportation of food essences

The limbs in particular are the Stomach and Spleens responsibility to nourish with food essence. It also has a major role in the transportation of food essences to the whole body. If the Stomach and Spleen are weak, so shall the person be (in particular the muscles). The pulse also shows Stomach health and activity: neither weak or strong, a balance between Yin and Yang qualities, and with a slow but regular beat shows good Stomach Qi. It also makes the pulse soft and gentle. The Stomach also reflects its health on the tongue coating. This coating is created by the same materials and processes that rot and ripen the foodstuffs. A thin white coat shows good health of the Stomach, no coat shows low Stomach Qi, thick white coat shows cold and thick yellow coat shows heat.

Controls the descending of Qi

The Stomach sends food downwards to the Small Intestine, this is why it is said that Stomach Qi goes down. If Stomach Qi rebels or goes upward, there can be heartburn, acid regurgitation, belching, hiccups, nausea, or vomiting. When digestion is harmonized the Liver Qi helps Stomach Qi descend, if the Liver Qi is stagnated the above symptoms can also arise.

Is the origin of fluids

Just as an essential medium is needed to extract the essence from herbs (water, alcohol, etc.), the same principle correlates to the Stomachs need of fluids to extract the essences from the food to be used by the body. If these fluids are plentiful, digestion will be normal. If these fluids are deficient, the patient will show thirst, bad breath, dryness on the tongue with possible cracks, and digestion will be poor. Stomach fluid deficiency is frequently caused by eating large meals late at night. The Stomach ensures that the parts from the food and drink which are not refined is turned into body fluids. This is why it is said that the Stomach likes wet and dislikes dryness. It is also said that if the Kidneys are not functioning properly in their role of fluid metabolism that the fluids will pour into the mid Jiao from the low Jiao and impair digestion. Conversely, if the Stomach fluids are deficient for a period of time, the chances of Kidney Yin deficiency is good. It should also be noted that the Stomach meridian is the only Yang meridian located on the anterior aspect of the body.

Effects of mental function

The Stomach often displays disease patterns of excess such as fire or Phlegm-fire. This can effect the mind. It can manifest as anxiety, confusion, hyperactivity, someone shutting themselves in the house, closing all the doors and windows, wanting to be alone, violent behavior, and taking off clothes in public (these all would be referred to today as manic behavior).

Effects dreams

“When the Stomach is deficient, one dreams of having a large meal.” (Spiritual Axis).

Close relations with the Spleen

Both the Stomach and Spleen belong to Earth element in the five element theory. These two organs are considered to be the Yin and Yang aspects of the same system of functioning. The Stomach is Yin and the Spleen is Yang. Stomach Qi descends, Spleen Qi ascends. The Stomach likes wetness, The Spleen likes dryness. The Stomach easily gets excess patterns of disease or deficiency of Yin and heat, the Spleen most often suffers from patterns of deficiency of Yang and cold.