In 576BC, when most of the world believed that diseases were caused by evil spirits, a traditional Chinese medicine practitioner, Yi He, suggested that an imbalance of six factors (yin, yang, wind, rain, night and day) could explain how ailments occurred. From this, physicians developed six key climatic influences: wind, cold, summer-heat, dampness, dryness and fire or heat. They’re commonly referred to as “evils”. The correlation between climate and disease is a way for TCM to explore imbalances of the body. Differentiating the “exogenous evils” based on specific symptoms – rather than identifying bacteria, viruses, toxins or parasites as causes for infectious diseases – allowed for a largely successful method of treatment for centuries in China. For example, bacterial dysentery was said to result from a damp-eat invasion of the large intestines. Under normal circumstances, climate doesn’t cause disease because the body adapts. But in cases of extreme environmental changes – or when the body is too weak to adjust – it can. Modern Chinese medicine physicians generally view the six evils as climatic factors, organisms or toxic materials that disturb the dynamic equilibrium within the body. Here are some of their symptoms: Wind evils can cause symptoms such as headaches, sweating, and aversion to windy conditions, tremors, convulsions, migrating joint pain and itchiness. Diseases are characterized by sudden onset, continual spreading, volatile and easily changeable physical symptoms. Cold evils cause symptoms such as chills, absence of sweating, pale complexion, slow pulse, cold limbs and muscle contractions. Related diseases are characterized by impaired organ function and sluggish blood circulation . Summer-heat evils cause symptoms such as high fever, irritability, flushed face, heart palpitations, excessive sweating, thirst and scant, yellowish urine. Related diseases are characterised by fidgeting, feeling irritable, a dispersal of chi (vital energy) and an overactive metabolism. These are usually accompanied by dampness evils. Dampness evils cause symptoms such as a heavy feeling in the head, lethargy, thick and turbid body secretions, chest distension, edema (generalized swelling) and urinary difficulty. Illnesses caused by dampness evils usually involve the spleen, which is responsible for some nutrient transformation and transportation functions. Dryness evils cause symptoms such as thirst, dryness in the mouth and throat, a dry cough, peeling skin, dull hair and constipation. Related diseases are characterized by fluid exhaustion and usually affect the lungs. Fire or heat evils are similar, but differ in intensity. Illnesses caused by fire, as opposed to heat, tend to be more severe. Associated symptoms include fever, thirst, sweating, irritability, anxiety, insomnia, bleeding problems and the appearance of boils and ulcers. Diseases are charcterised by inflammation, exhaustion of bodily fluids and disturbances in chi and blood flow. Rose Tse and Angela Collingwood are editors for Shen-Nong, a subsidiary of Integrated Chinese Medicine. Before taking any medicine, consult your TCM or general practitioner. Rose Tse and Angela Collingwood info@shen-nong.com Edited by Suzanne Harrison suzanne.harrison@scmp.com Published: May 16, 2005 Source: South China Morning Post