Cornus (Cornus officinalis) is a tree used in Chinese medicine. Its Chinese name is shan zhu yu. Cornus is shrub that grows to a height of 30 ft (10 m) in the woodland regions of East Asia from China to Korea. The fruit is used in healing. It is harvested when ripe, then dried for future use. The small fruits can also be eaten as food, either raw or cooked. They contain about 8.6% sugar and have a slightly astringent taste. The bark from the stem is also used as an anti-malarial tonic.
Chinese cornus should not be confused with the North American tree Cornus florida, better known as dogwood or American boxwood. Dogwood and Chinese cornus are in the same plant family but have somewhat different healing properties. The bark of Cornus florida is used in Western herbal healing.
Cornus has been used in China for more than 2,000 years. In the Chinese system of health, yin aspects must be kept in balance with yang aspects. Ill health occurs when the energies and elements of the body are out of balance or in disharmony. Health is restored by taking herbs and treatments that restore this balance.
Cornus is strongly associated with the kidneys, the reproductive system, and, to a lesser extent, the liver. It is made into a slightly warm yin tonic and classified as having a sour taste. In Chinese medicine sour herbs are believed to help control body fluids and conditions such as bed-wetting, excessive sweating, heavy or prolonged menstruation, and premature ejaculation.
Cornus is rarely used alone. It is an ingredient in many herbal formulas where it is used to stabilize and bind. It has astringent properties that are thought to boost the power of other herbs. Cornus can be combined with both yin and yang herbs to remedy deficiencies in either area because it conserves jing, the essence of life. In Chinese medicine jing, when referring to a man, means sperm. The ability to conserve jing is a result of the stabilizing and binding properties and the ability to control body fluids.
Although the results are not completely clear, some studies have shown that the fruit of cornus has antibacterial and antifungal properties. In some studies extracts of the fruit inhibited the growth of some strains of Staphylococcus bacteria. It may also be effective against Salmonella and Shigella, both bacteria that cause gastrointestinal disturbances.
Cornus fruit is also used in formulas that strengthen the back and knees, both areas associated with kidney jing. It is also used in formulas that control body fluids and treat excessive sweating, urine leakage, sperm leakage (spermatorrhea), and heavy, prolonged menstruation. Cornus is also an ingredient in formulas that treat ringing of the ears (tinnitus), poor hearing, dizziness, extreme shock, and a wide range of other conditions. The bark is boiled, and the resulting astringent decoction is used in formulas that treat fevers and as an anti-malarial. Interestingly, in Western herbalism the bark of dogwood, cornus's cousin, is also used against malaria. Cornus is also used to treat diabetes, arthritis, and impotence.
Two Chinese studies published in 1997 and 1998 in The American Journal of Chinese Medicine found that extracts of cornus increased the blood flow to the kidney and spleen and increased the motility of human sperm. Few scientific studies have been done on this herb out-side of China.
Both cornus fruit and bark usually are prepared as a decoction that can be added to other tonics and healing formulas. They can also be prepared as a tincture. The dosage varies depending on the formula.
Some formulas that contain cornus include:
- eight immortal long life pill
- supreme creation
- Buddha's yang
- dragon jing
- endocrine health
- essence restorative
People experiencing painful or difficult urination should not use cornus.
Since cornus is rarely used alone, it is difficult to separate any side effects it may cause from those caused by other herbs in the formula. No side effects have been reported.
Cornus is has been used for thousands of years in conjunction with other herbs with no reported interactions. Since cornus is used almost exclusively in Chinese medicine, there are no studies of its interactions with Western pharmaceuticals. Although it should not be used while taking a diuretic since cornus is an antidiuretic.
Molony, David. Complete Guide to Chinese Herbal Medicine. New York: Berkeley Books, 1998.
Teegaurden, Ron. The Ancient Wisdom of the Chinese Tonic Herbs. New York: Warner Books, 1998.
American Association of Oriental Medicine. 433 Front Street, Catasauqua, PA 18032. (610) 266-2433.
Plants For a Future. The Field, Penpol, Lostwithiel, Cornwall, PL22 0NG, England. (+44 1208) 872963. http://www.scs.leeds.ac.uk/pfaf/.
Healthlink Online. http://www.healthlink.com.au/.