When Traditional Chinese Medicine (TCM) refers to Humidity, it mainly refers to atmospheric humidity, that is to say the water vapor contained in the air. Although humidity is usually invisible, we can feel its presence very well. At 10% relative humidity, the air seems dry to us, at 50% it is comfortable, at 80% we feel a certain heaviness, and in the neighborhood of 100%, the humidity begins to condense: fog, haze and even rain appear.

TCM considers Moisture to be heavy and sticky. Rather, it tends to descend or stand close to the ground, and it feels like it’s hard to get rid of. We like to associate it with something dirty or cloudy… fungi, molds and algae thrive in humid environments. It is from these particular characteristics of Moisture that TCM qualifies different states of the organism. So, when we say that functions or Organs are affected with Moisture, it does not mean that they have suddenly become engorged with water or that their environment has just become humid. Rather, we want to illustrate, by analogy, that their clinical manifestations are analogous to the characteristics that Humidity demonstrates in nature. Here are a few examples:

• If the Moisture reaches the Stomach, we will have a heavy digestion with the unpleasant feeling of having a full Stomach and no longer having an appetite.
• If the Humidity stagnates in the Lung, breathing is more labored, the breath passes less well and we feel a sensation of excess in the chest (as in a very humid sauna).
• Moisture can also block the normal circulation of body fluids. In this case, it is not uncommon for people to experience swelling or edema.
• Moisture is sticky: the diseases it causes are difficult to cure, their evolution is long, they last a long time or they occur in repetitive crises. Osteoarthritis, which develops gradually over several years, is a good example. In fact, people with osteoarthritis experience more severe pain on wet and rainy days.
• Humidity is heavy: it is associated with sensations of heaviness in the head or in the limbs. We feel tired, we have no strength.
• Moisture is “unsuitable” in nature: it contributes to the production of wax at the edges of the eyes, oozing in case of skin diseases, abnormal vaginal discharge and cloudy urine.
• Moisture is stagnant, it tends to stop the movement: when the normal movement of a viscera does not take place, Moisture is often the cause.

TCM considers that there are two types of Moisture: external and internal.

If we are exposed to high humidity for a long time, for example by living in a damp house, working in a humid climate, or by standing for a long time in the rain or sitting on damp ground, this will promote the invasion of External moisture in our body. The simple fact of living in a poorly ventilated basement makes many people feel heavy, tired or oppressed in the chest.

When Moisture enters the tendon-muscular meridians, which are the most superficial (see Meridians), it blocks the flow of Qi and causes a feeling of numbness. If it gets into the joints, they become swollen and you feel dull aches and pains. In addition, bones and cartilages are deformed under the effect of moisture. Finally, many rheumatoid pathologies, such as arthritis deformans and osteoarthritis, are linked to external humidity.

Our parents told us not to keep our feet wet or else get a urinary tract infection… Chinese parents probably teach their children the same thing, as Moisture can enter through the Kidney Meridian – which begins under the foot and that goes up to the Bladder – and cause a feeling of heaviness in the lower abdomen, the feeling of not being able to completely empty the Bladder, and cloudy urine.

The transformation and circulation of body fluids are managed by the Spleen / Pancreas. If the latter is weak, the transformation of Liquids will be deficient, and they will become impure, transforming into Internal Moisture. In addition, the circulation of Liquids being affected, they will accumulate, causing edemas and even internal humidity. The symptoms relating to the presence of internal humidity are the same as for external humidity, but their onset is slower.

If internal moisture remains for a while, it may condense and turn into phlegm or phlegm. While Moisture is invisible and can only be seen through symptoms of illness, phlegm is clearly visible and more easily causes blockages. For example, if the lung is blocked by phlegm, you will see coughing, sputum of phlegm, and feelings of tightness in the chest. If it reaches the upper respiratory tract, the phlegm can lodge in the sinuses and cause chronic sinusitis.