Traditional Chinese Medicine views the cause of disease in three main areas: external causes, internal causes, and a group of miscellaneous causes which primarily involve lifestyle. These are outlined below:
The Six External Causes
The six external causes of disease, also known as the six evils, are causes of disharmony that relate to climatic conditions. Just as extremes of wind, cold, heat, dampness, dryness, and summer heat can have devastating effects on the world in which we live, they can also seriously alter the balance within the body by diminishing, or blocking the flow of qi in the organs.
Wind is the most prevalent of the six external factors, and refers to the ability of an illness to spread within the body. Symptoms commonly linked with wind include chills, fever, colds, flu, nasal congestion, headaches, allergies, arthritic and rheumatic conditions, as well as dizziness and vertigo.
Cold related imbalances manifest as conditions that diminish the body's immune system, such as colds, cough, upper respiratory allergies, as well as poor circulation, anemia, and weak digestion.
Heat conditions are described as hot and inflammatory, exacerbated by hot weather and exposure to direct heat. They represent an over-active metabolic process, which can result in hypertension, hyperthyroid, ulcers, colitis, inflamed arthritic joints, as well as flu and skin rashes.
Dampness symptoms are created through the intake of oily and fluidic foods, as well as wet weather. These symptoms may include swelling, obesity, the formation of cysts, tumors, and lumps, and an increased production of phlegm. This phlegm production can affect the sinuses and upper respiratory passages, including the lungs and bronchioles.
Dryness can damage vegetation, and creates similar imbalances within the body, causing disorders of the lungs, sinuses, large intestine, skin, digestion, and reproductive organs.
Summer Heat, or an overexposure to sunlight and hot weather, can yield conditions such as heat stroke, dizziness, nausea, extreme thirst, and exhaustion.
The Seven Internal Causes
The seven internal causes, otherwise known as the Seven Emotions, are illnesses brought about by intense, prolonged, or surpressed feelings, and are defined as follows:
Sadness decreases the flow of qi in the lungs and heart, and is associated with depression, fatigue, amenorrhea, shortness of breath, asthma, allergies, cold and flu.
Grief is similar to sadness, and injures the lungs, decreases immunity to colds and flu, as well as chronic upper respiratory diseases such as emphysema, allergies, and asthma.
Pensiveness, or over-engaging the mind in activities such as worry, thought, or study can deplete spleen qi, and may result in edema, digestive disorders, low appetite, and fatigue.
Fear, or paranoia causes qi to descend, resulting in potential harm to the kidneys, lower back, or joints when this emotion is ever present.
Fright, or shock is unlike fear in the sense that the onset is very sudden, causing one's qi to diverge. The rapid change in flow first affects the heart in symptoms such as breathlessness and palpitations, then moves to the lower body in a similar fashion to fear, damaging the kidneys, lower back, and joints.
Anger encompasses all the negative emotions of rage, irritability, frustration, and resentment, and causes the qi to rise inappropriately. Anger is associated with headaches, mental confusion, dizziness, and hypertension.
Joy in Chinese Medicine refers to excess, or overabundance, and relates to illness relative to overindulgence. Damage to the heart may result, and the conditions of hysteria, muddled thought, and insomnia may arise.