In Chinese medicine the Stomach is the organ of digestion of food and nourishment of the body. It receives and "ripens" ingested food and drink. It is also responsible for the absorption of nutrients from the food into the blood stream. It corresponds in physiological terms to the stomach, duodenum and the first 10 cm of the small intestine, where the absorption of nutrients takes place.
The Stomach has a paired relationship with the Spleen; the Spleen rules ascending whilst the Stomach sends material down: the pure part to the Spleen and the remainder to the Small Intestine for further digestion. If the receiving and descending functions of the Stomach are impaired, symptoms such as nausea, stomach ache, distention, belching or vomiting may ensue.