Full of Hot Air: China's Summer Colds

2016-08-22   Source: The World of Chinese

There are times when the classic scriptures of traditional Chinese medicine (TCM) read like an account of the body in an endless struggle for equilibrium. According to the The Yellow Emperor’s Classic of Internal Medicine 《黄帝内经》, China’s earliest book of TCM knowledge, the human body, as with all things in the universe, is sustained by the balance of the forces of yin and yang. This delicate apportioning of forces in the body is liable to being upset by everything including changes in the weather and the foods we eat. Under the idea that “people and heavens are mutually related” (天人相应), the basic precepts to health maintenance (养生, literally “life cultivation”) under TCM is that one should respond to changes to the body’s external environment—usually weather or seasonal change—by adjusting one’s diet, activity level and even emotional state.

Nowhere is this idea more evident than in the oxymoron known as the summer cold, contradictory in its name as well as its nature, striking at the apex of summer just when everything cold and winter-related has become the merest memory. But according to Chinese medicine, it is exactly our insistence in trying to bring back the “cold” rather than embracing the summer heat causes this insidious disease to strike.

The Chinese language avoids the contradiction of speaking of the “summer cold” by referring to the common cold as ganmao (感冒), which refers to a feeling of being “under” or suppressed. As in the English expression of feeling “under the weather,” suffers of ganmao feel that they are under 风邪 (fengxie, also the Japanese word for the common cold), or an abnormality in the winds that is blamed for a host of health conditions in Chinese medicine from fever to numbness to hives; the Yellow Emperor’s Classic states at least twice that “wind is the cause of hundreds of afflictions” (风者，百病之始也). An older folk term for the cold, found in many ancient works of TCM, is simply 伤风, or the condition of being harmed by wind. While understanding the finer points of wind’s relation to health isn’t possible without deep study of centuries of TMC literature, the basic idea is that the wind is one of the phases taken by the qi, the essence of life, as it passes through the seasons. The body catches the “harmful wind” when changes to the qi inside the body are not in sync with the qi of the outside.

While conventional wisdom in the West associates the cold with the fall and winter season, as defined by institutions such as the US Center for Disease Control, the wind is the phase of qi associated with spring in TCM. Colds, however, can be caught in any season, and there are different classifications of the illness depending on the exact type of wind imbalance of a particular season. The two main types are 风寒感冒 (“wind and cold cold”) and 风热感冒 (“wind and heat cold”). The former is associated with the fall and winter, and is thought to be caused by the qi in one’s lungs losing circulation when transitioning into the season of cold winds. The latter type of cold is associated with the spring and early summer, and is caused by imbalance between the colder air in one’s lungs and the warm winds outside. There are two other types of cold known as 暑湿感冒 (“summer heat humidity cold”) and 暑热感冒 (“summer heat heat cold”) associated with the peak of summer. These are thought to be caused by imbalance between the hot or humid outside air and the cooler and dry air in one’s body, which result as one tends to stays indoors, consume cold foods and drink, and try various other methods of cooling down during summer. The folk term for the summer cold is simply 热感冒 or 热伤风 (“hot cold” or “hot wind harm”).

Curiously, modern TCM and conventional medicine agree on the condition that most commonly leads to or exacerbates the summer cold today: the use of air-conditioning indoors during summer. While the TCM explanation is that cold, dry, air-conditioned air in the body causes harm when juxtaposed against the warm, humid air outside, the view of modern immunology is that dry, air-conditioned air dries out the mucus lining in the nasal passage and causes blood vessels to constrict, which reduces the amount of white blood cells flowing into the upper respiratory system. Both of these effects reduce the body’s resistance to the cold virus.

Actually, taking away most of TCM’s philosophical trappings, most of its descriptions of the cold bear surprising similarity to conventional medicine. It is acknowledged in modern immunology, for example, that colds are caused by different types of viruses in different seasons and lead to different symptoms: upset stomach is considered to be a property of the summer cold viruses, while digestive problems are also associated with the “summer humid cold” along with sweating, fatigue, and aches. Both types of medicine recommend hand-washing as a preventative measure for the cold, while TCM additionally recommends washing the hands and feet. In the view of TCM, these measures help improve the circulation of blood, an important facet to boosting the body’s immunity in both conventional medicine and TCM because it either improves the distribution of white blood cells or of qi throughout the body. Finally, both medical traditions cite stress as a factor that reduces the body’s immunity to cold—TCM recommends keeping a “positive attitude”—while mild exercise can alleviate the symptoms.

In essence, while ancient Chinese medical wisdom never detected the microbial root causes of the illness, they were spot-on in their own way as to many of its symptoms and treatments. Throughout the centuries, symptoms of the “wind harm” have been catalogued and discussed in countless TCM classics from the Sui Dynasty’s On the Origin and Symptoms of All Disorders (《诸病源后论》, written in 610) to the Song Dynasty’s Formulas Related to the Unification of the Three Etiologies (《三因极一病证方论》, written in 1174), which proposed its own classification of “wind harm” into six types according to the location of the ailment TCM’s “six stages” of disease progression, a system first developed in the map the yin and yang passageways of energy throughout the body. This produced a humorously specific and complicated list of symptoms: wind harm in the taiyang meridian, for instance, leads to high temperature, chills, “autonomic sweating” (自汗, without being induced by physical exercise), rigidity at the nape of the neck, pain in the lumbar area, and one’s pulse being close to the surface; it is best treated with a brew of Chinese cinnamon. In the yangming meridian, the patient has a temperature, fullness in the abdomen, thirst, “autonomic sweating,” “fondness for sleeping” (嗜卧), heaviness in the body, trouble urinating, and a pulse that is shallow and quick, which are all best treated with a brew of apricots. On the other hand, when one has a cold in the taiying meridian, one experiences autonomic sweating, fullness in the chest, pain in the abdomen, slow diarrhea, and a strong, slow pulse, best treated with a brew of Chinese cinnamon and peony.

These days, TCM remains a controversial practice and further research is required into many of its doctrines in order to distinguish between knowledge that is useful, erroneous, or useful in practice without being theoretically sound. In the meantime, simply take it as reminder to be mindful of our health whatever the season.