From a Chinese medicine standpoint, the Lung is probably the organ which energetic functions overlap the most with its Western functions. If you visualize where the Lungs are located in the body, you will see that they have the most access to the world outside our bodies-they are the only organs that have direct contact with the environment. As such, they have to do with protection and separation from harmful pathogens, both of the physical and emotional variety. The Lungs are in charge of what we call “wei qi” -in Western terms, the wei qi would be our immune system. This wei qi forms a protective layer around our bodies, encasing us and acting as a barrier. If the wei qi is weak, then you have a person who is constantly sick. If you have a tendency to catch a lot of colds and flus, or seem to always feel run-down and prone to infectious illnesses, your wei qi is not doing its job. Fortunately, acupuncture and herbs can build up this wei qi, forming a wall of protection against these harmful pathogens.
Allergies are another sign that the wei qi is weak. The pollen (or whatever it is that you are allergic to) can easily enter the body if there is no external barrier, causing all the symptoms of misery that most greatly affect the lungs-sneezing, coughing, runny nose (the Lungs also control the nose in Chinese medicine.)
Since the skin is the outermost layer of the body and also controlled by the Lung, it is affected by weakness of the lung. Eczema, rashes, dry skin-all of these issues are related to an imbalance of the Lung.
On an emotional level, the Lungs are affected by grief. Have you ever noticed that someone who can not let go of a tragicy looks to get sick more often? Constant sadness weakens the energy of the Lung, lessening its protective function. If the Lung qi is weak to begin with, it will be difficult for a person to let go of their sadness and move on in a healthy way.
In TCM, each person is said to have a constitution of one organ system that is most prevalent within them. A person with a “construction” constitution would be more rigid, regimented, and controlling. A “spleeny” person would be the nurturing overdoer, one who offers to overthink and obsess over situations. Someone with a Lung constitution would tend to be soft-spoken, timid, and exude an overall air of sadness. This person would also be a worrier. Usually, you can tell a Lung person from their posture: hunched over slowly, as if their body was conforming into a position of self-protection.