The relationship between the lungs and the spleen is mainly manifested in the two aspects of qi generation and fluid metabolism.
1. Generation of qi. The lungs are responsible for respiration and inhalation of clear air in nature; the spleen is responsible for transportation (the spleen has the function of digesting food, absorbing food essence and water and transferring it to the whole body), generating water and grain essence. The water and grain essence produced by the spleen relies on the lung qi to transport it throughout the body, and the water and grain essence needed for the physiological function of the lungs relies on the spleen qi to transport it.
Whether lung qi deficiency affects the spleen or spleen qi deficiency affects the lungs, it can ultimately lead to both lung and spleen deficiencies, which can be characterized by coughing and shortness of breath, poor appetite and tiredness, abdominal distension and loose stools (thin and unshaped feces), and so on.
2. Fluid metabolism. Lung qi declares and descends, the main line of water so that the normal distribution and excretion of fluid; the spleen is the main transport, water and drink upward transmission in the lungs or spleen qi disperses the essence, so that the normal generation and distribution of fluid, the lungs and spleen, two organs, coordinated and cooperating with each other for the purpose of ensuring that the normal distribution and excretion of fluid.
In addition, the spleen’s failure to transport the fluid stops, affecting the lung qi declination; the lung’s failure to declination, the waterway is not smooth, water and dampness trapped in the spleen, the interaction of the two organs can lead to abnormal distribution of fluid, the formation of phlegm (a pathological product of impaired metabolism of water), edema, and so on.