Parts Used & Where Grown
Wild yam plants are found across the midwestern and eastern United States, Latin America (especially Mexico), and Asia. Several different species exist. All of which possess similar constituents and properties. The root is used medicinally.
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3 Stars Reliable and relatively consistent scientific data showing a substantial health benefit.
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1 Star For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.
This supplement has been used in connection with the following health conditions:
Refer to label instructions
Wild yam has been reported to raise HDL (“good”) cholesterol in preliminary research.
Wild yam has been reported to raise HDL cholesterol in preliminary research. Doctors sometimes recommend 2 to 3 ml of tincture taken three to four times per day, or 1 to 2 capsules or tablets of dried root taken three times per day. 2
Refer to label instructions
Wild yam is an herb with weak estrogen-like actions similar to soy. In one trial, a formula containing licorice, burdock, dong quai, wild yam, and motherwort reduced menopause symptoms.
A variety of herbs with weak estrogen-like actions similar to the effects of soy have traditionally been used for women with menopausal symptoms.3 These herbs include licorice , alfalfa , and red clover . In a double-blind trial, a formula containing tinctures of licorice, burdock , dong quai , wild yam , and motherwort (30 drops three times daily) was found to reduce symptoms of menopause.4 No effects on hormone levels were detected in this study. In a separate double-blind trial, supplementation with dong quai (4.5 grams three times daily in capsules) had no effect on menopausal symptoms or hormone levels.5 A double-blind trial using a standardized extract of subterranean clover (Trifolium subterraneum), a relative of red clover , containing 40 mg isoflavones per tablet did not impact symptoms of menopause, such as hot flashes, though it did improve function of the arteries.6 An extract of red clover, providing 82 mg of isoflavones per day, also was ineffective in a 12-week double-blind study.7 In another double-blind study, however, administration of 80 mg of isoflavones per day from red clover reduced the frequency of hot flashes in postmenopausal women. The benefit was noticeable after 4 weeks of treatment and became more pronounced after a total of 12 weeks.8
Traditional Use (May Not Be Supported by Scientific Studies)
Wild yam has been used by herbalists as an expectorant for people with coughs . It was also used for gastrointestinal upset , nerve pain, and morning sickness .1 Eventually, it was discovered that the saponins from wild yam could be converted industrially into cortisone, estrogens, and progesterone -like compounds. Wild yam and other plants with similar constituents continue to be a source for these drugs.
How It Works
How It Works
The steroidal saponins (such as diosgenin) account for some of the activity of wild yam. Another compound, dioscoretine, has been shown in animal studies to lower blood sugar levels.9 An extract of wild yam was also found in a clinical trial to have antioxidant properties and raised HDL, the “good,” cholesterol in elderly adults.10
Contrary to popular claims, wild yam roots do not contain and are not converted into progesterone or dehydroepiandrosterone ( DHEA ) in the body.11 , 12 Pharmaceutical progesterone is made from wild yam using a chemical conversion process. This can lead to confusion—while wild yam can be a source of progesterone, it cannot be used without this pharmaceutical conversion, which cannot be duplicated by the body. Women who require progesterone should consult with their physician and not rely on wild yam supplements.
How to Use It
Up to 2–3 ml of wild yam tincture can be taken three to four times per day. Alternatively, 1 gram of dried, powdered root can be taken three times each day.13
Interactions with Supplements, Foods, & Other Compounds
Interactions with Medicines
Some people may experience nausea or vomiting when taking large amounts of wild yam (several times the recommended amounts). The safety of wild yam during pregnancy and breast feeding has not been established.
1. Lust JB. The Herb Book. New York: Bantam Books, 1974, 401.
2. Araghiniknam M, Chung S, Nelson-White T, et al. Antioxidant activity of dioscorea and dehydroepiandrosterone (DHEA) in older humans. Life Sci 1996;11:147–57.
3. Crawford AM. The Herbal Menopause Book. Freedom, CA: Crossing Press, 1996.
4. Hudson TS, Standish L, Breed C, et al. Clinical and endocrinological effects of a menopausal botanical formula. J Naturopathic Med 1997;7(1):73–7.
5. Hirata JD, Swiersz LM, Zell B, et al. Does dong quai have estrogenic effects in postmenopausal women? A double-blind, placebo-controlled trial. Fertil Steril 1997;68:981–6.
6. Nestel PJ, Pomeroy S, Kay S, et al. Isoflavones from red clover improve systemic arterial compliance but not plasma lipids in menopausal women. J Clin Endocrinol Metab 1999;84:895–8.
7. Tice JA, Ettinger B, Ensrud K, et al. Phytoestrogen supplements for the treatment of hot flashes: the Isoflavone Clover Extract (ICE) Study: a randomized controlled trial. JAMA 2003;290:207–14.
8. van de Weijer PHM, Barentsen R. Isoflavones from red clover (Promensil®) significantly reduce menopausal hot flush symptoms compared with placebo. Maturitas 2002;42:187–93.
9. Iwu MM, Okunji CO, Ohiaeri GO, et al. Hypoglycaemic activity of dioscoretine from tubers of Dioscorea dumetorum in normal and alloxan diabetic rabbits. Planta Med 1990;56:264–7.
10. Araghiniknam M, Chung S, Nelson-White T, et al. Antioxidant activity of dioscorea and dehydroepiandrosterone (DHEA) in older humans. Life Sci 1996;11:147–57.
11. Araghiniknam M, Chung S, Nelson-White T, et al. Antioxidant activity of dioscorea and dehydroepiandrosterone (DHEA) in older humans. Life Sci 1996;11:147–57.
12. Dollbaum CM. Lab analyses of salivary DHEA and progesterone following ingestion of yam-containing products. Townsend Letter for Doctors and Patients Oct 1995:104.
13. Bertram T. Encyclopedia of Herbal Medicine. Dorset, England: Grace Publishers, 1995, 454.
Last Review: 11-07-2012
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The information presented in Aisle7 is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires June 2013.
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