Originating in China several millennia ago, traditional Chinese medicine is based on the theory that illness results from the imbalance of the life force (qi, pronounced chee) through the body. Qi is restored by balancing the opposing forces of yin (dark, feminine, negative forces) and yang (bright, masculine, positive forces), which manifest in the body as cold and heat, internal and external, and deficiency and excess. Various practices are used to preserve and restore qi and thus health.
Most commonly used are
Other practices include diet and massage.
Traditional Chinese medicine uses formulas containing mixtures of herbs to treat various ailments. Determining whether these mixtures are safe and effective is difficult. One problem is that standardization and quality control are almost nonexistent. Thus, the following can result:
Because mixtures can vary so much and because there are so many mixtures that could be studied, most conventional research usually studies one herb, not a mixture. However, one herb, used alone rather than as a part of a mixture, may not be considered effective by traditional practitioners.
Chinese herbal mixtures have been used to treat irritable bowel syndrome, rheumatoid arthritis, and many other disorders. For the most part, evidence that these mixtures are effective for any disorder is lacking, although some evidence suggests that some herbs and herbal mixtures may be beneficial. For example, some evidence suggests that the herb Astragalus may improve quality of life for people being treated with chemotherapy for lung cancer. However, it does not prolong life or slow the progression of cancer. In such cases, more research is needed to determine whether the herbs are effective.
Each herb and mixture may have its own unique side effects. For example, an herb called ma huang (Ephedra), an ingredient in many remedies, is a stimulant that can increase heart rate and blood pressure and thus increase the risk of stroke or heart attack.
In herbal mixtures, adverse effects may also result from interactions between active ingredients.