Stomach

The Stomach meridian (Zu Yang Ming Wei Jing) is one of the twelve principal channels of Chinese medicine, the network along which qi is held to circulate through the body. It is a Yang channel, paired with the Stomach, and belongs to the phase of Earth in the five-phase (wu xing) scheme.

Function in the tradition

In the theory of the channels this meridian is concerned with the receiving and first ripening of food, the root of acquired nourishment. The twelve principal channels are arranged in yin-yang pairs and in a daily cycle through which qi is said to pass from one to the next, and the points along them are those used in acupuncture and related therapies.

The meridian is described here as a concept of traditional Chinese medicine, a system of ideas and practice with a long documented history, rather than as an anatomical structure of Western physiology.

The Daily Cycle and Its Length

Qi is said to pass through the twelve channels in a fixed daily sequence, an idea present in outline in the Huangdi Neijing though the specific two-hour timetable now taught, called Ziwu Liuzhu, was worked out later, in the Jin and Yuan periods of the twelfth and thirteenth centuries. In that scheme the Stomach channel governs seven to nine in the morning, and at forty-five points running from below the eye to the second toe it is also the longest of the twelve principal channels. Paired with the Spleen as the two channels of the Earth phase, the pair is together called houtian zhi ben, the root of postnatal qi, the source from which food and drink become the qi and blood the rest of the body draws on.

The Stomach channel is the principal yang channel of the front of the body, which is unusual in itself: yang channels in this system generally run on the outer and posterior surfaces, and the Stomach is the conspicuous exception, descending the face, chest, abdomen and the front of the leg to the second toe. The tradition explains the anomaly by function rather than geography, since the Stomach is described as the origin of the acquired qi, what the body makes from food, as against the inherited qi stored by the Kidney.

Its best known point is Zusanli, Stomach 36, below the knee. The name is usually rendered Leg Three Li, a li being a unit of distance, and the classical literature attaches to it a reputation for restoring a tired traveller enough to walk three more. It is among the most heavily studied points in the modern acupuncture literature and among the most heavily used in the classical, and the atlas records both facts without asserting an effect.

The Stomach pairs with the Spleen as the yang and yin of the Earth phase, and the two together carry most of what Chinese medicine says about digestion, appetite and the transformation of food. That is a statement about the tradition's own model. It is not an anatomical claim, and nothing here is medical advice or a reason to defer a medical question to anyone but a clinician.