Description |
Goldenseal (Hydrastis canadensis), is a member of the Ranunculaceae family. Goldenseal is a perennial that grows in the wild from Georgia to Canada. The plant grows from a yellowish root and forms a hairy stem with five-parted leaves, green white flowers with no petal and a fruit that resembles a raspberry. In the 19th century, the expansion of farming lands and the popularity of its medicinal properties among the early settlers and Native American Indians led the plant to become an endangered species. It is now cultivated and its high price and demand may result in adulterated products. As a result of the endangered status of goldenseal, a handful of environmentally conscious supplement companies have taken the position of substituting other berberine-containing herbs for goldenseal in their immune support formulas. Other plants that contain relatively high concentrations of Berberine (the alkaloid thought to contribute to the immune-stimulating effect of Goldenseal) include Goldenthread (Coptis chinensis), Oregon Grape (Berberis aquifolium), Barberry (Berberis vulgaris), and Tree Turmeric (Berberis aristata). |
Claims |
|
Theory |
Goldenseal contains several alkaloids in its roots, stems and leaves that are believed to be the active components: hydrastin (4%), berberine (6%) and canadine. Berberine possesses some antibacterial activity by either directly killing bacteria or preventing bacterial attachment to the cell walls of the host, as well as some antioxidant properties and smooth muscle relaxation effects. |
Scientific Support |
No scientific human studies evaluating the
effect of
Goldenseal have been reported at this point. Only animal, animal tissue
and in-vitro testing have been done at this point and there is a long
history of folk-medicine use of
Goldenseal. A recent placebo controlled animal (rats) study tested the
effectiveness of
Goldenseal as an “immunostimulant.” The study measured the formation of
specific antibodies in rats injected with an antigen (a compound that
stimulates an immune response). An extract of
Goldenseal root was consumed (in the rats’ drinking water) for 6 weeks.
Results of the study indicated that goldenseal caused a significant increase
in antibodies (IgM) from day 1 to day 15 when compared to the control group,
but that this benefit disappeared after day 15. A similar experiment was
done using an
Echinacea extract – showing that the animals receiving
Echinacea had increased antibodies (IgG) from day 1 to day 27, but this
benefit also disappeared by day 25 Berberine, one of the alkaloids found in Goldenseal, was found to decrease the activity of an enzyme involved in tumor growth (arylamine N-acetyltransferase) in a colon cancer cell culture. Whether Goldenseal supplements would have any effect on colon cancer in humans remains to be tested. |
Safety |
Goldenseal is generally considered safe – but it should not be used
during pregnancy or lactation and should be avoided by individuals with high
blood pressure or other cardiovascular diseases. Goldenseal is often found in combination with Echinacea and is claimed to help in the treatment of upper respiratory infections. No well-designed studies back this claim. The immunomodulation benefits of Goldenseal root extract have been shown in a recent study on laboratory animals but the extrapolation of these results to a human population exposed to different antigens or microorganisms may not be applicable. |
Dosage |
Recommended doses of the powdered root range from 4 to 6 grams per day. Dosage of the root extract ranges from 250 to 500 mg three times per day and may be standardized to berberine or total alkaloid levels (approximately 5%). Continuous use should not exceed three weeks. |