Functions of the Lungs
The Lungs governs diffusion and downbearing.
Commentary: The Lungs nourish the skin and body hair and protect the exterior against invading pathogens. The diffusion aspect, which is one aspect of the Lungs's function to govern Qi, is responsible for ensuring the movement of Qi and sending the Defense-Wei-Qi outward to the body surface. On the body surface, the Defense-Wei-Qi protects us from the invasion of pathogenic factors. Dryness is to be said in the Five- Elements-Theory, to be the main pathogen affecting the Lungs. But if the Defense-Wei-Qi is weak, the Lungs can be attacked by all pathogenic factors, since the Lungs are the most exterior organ and the breathing function connects the Lungs to the outside world. The strength of the immune system and the ability to prevent invasion of pathogenic factors is based on the harmonious function of all the organs involved in Qi production. The Kidneys are the source of a strong immune system, nourished by the Food Qi of Spleen and Stomach, and distributed through the Lungs. The Lungs govern the waterways which is a combination of the two functions of diffusion and downbearing. Diffusion means that fluids are distributed throughout the body and to the skin, where they leave the body in the form of sweat. Downbearing means that wastewater is conveyed to the Kidneys and Bladder to be discharged. The Lungs send Qi and Body Fluids to the Kidneys. The Kidneys in turn must be able to hold the Qi and Body Fluids. If the Lungs are not able to maintain this function, Stagnation develops in the Lungs, causing weakness in the Kidneys. If the downbearing function is impaired, edema, mostly in the upper body, can develop.