Wild Yam

Wild yam is an important tool for making medicine. Explore more about its ancient origins, different varieties, ways to consume it safely, and the ideal environment for its cultivation.

Quick Facts
General Information
  • Common name(s)Wild yam, Mexican yam, Chinaroot, colic root
  • Scientific nameDioscorea villosa
  • Plant typeVegetable
  • Native regionAmericas, North America
  • Main producer(s)United States of America
  • Main Economic UseMedicinal
Wild Yam

Wild yam has a long history of alimentary and medicinal uses that can be traced back to Native American cultures, before the arrival of the first European settlers. Modern science has revealed the mechanisms behind wild yam's health benefits and expanded its uses to the pharmaceutical industry; however, the folk applications of the herb remain popular among herbalists.

Medicinal and Nutritional Information

Quick Facts (Medicinal and Nutritional Information)
  • Medicinal actionHormone balancer, Hypocholesterolemic
  • Key constituentsDiosgenin
  • Ways to useCapsules, Liquid extracts, Ointment
  • Medicinal rating(2) Minorly useful plant
  • Safety rankingUse with caution
Wild Yam

Health Benefits of Wild Yam

Wild yam is a unique herb with a very specific set of properties. Scientific studies have been inclusive about its effectiveness in direct consumption, and its claimed benefits are yet to be fully corroborated. Nevertheless, wild yam is popularly used for the following purposes:

  • Treating hormonal imbalances. It is thought that wild yam helps regulate menstrual cycles and supports uterine health in menopausal and postmenopausal women.

  • Reducing cholesterol levels. Some research suggests that wild yam may stimulate the excretion of cholesterol, thus preventing the accumulation of plaque in the arterial walls.

Additionally, wild yam promotes liver health and it is believed to help relieve the symptoms of rheumatoid arthritis.

How It Works

The main compounds in wild yam are steroidal saponins, chiefly diosgenin. Minor saponins are methylprotodioscin, disoscin, and prosapogenin A, as well as flavan-3-ol glycosides.

Flavonoids and phytosterols - including sitosterol, stigmasterol, and taraxerol - have also been found in wild yam, as well as dioscorine, tannins, starch, vitamin C (ascorbic acid), and beta-carotene.

Wild yam has been found to contain about 3.5% diosgenin, which is is used as a source in the synthesis of a sex hormone called progesterone, as well as for the production of cortisone and other steroids prescribed in hormone replacement therapy (HRT), which benefit women with fertility problems, irregular menstrual cycles, and hormone deficiencies due to menopause and post-menopause.

Diosgenin has shown antioxidative and hypolipidemic effects, inhibiting the pancreatic enzymes that aid cholesterol absorption, as well as protecting the liver from oxidative damage.

Diosgenin stimulates fat metabolism and increases bilis production, therefore improving cholesterol secretion and reducing the formation of triglycerides.

Black cohosh and goji berry also promote hormonal balance, whereas hypocholesterolemic properties can be found in flax and sacha inchi.

Wild Yam Side Effects

Large doses of wild yam taken orally can cause vomiting. Women who are breastfeeding or pregnant, as well as those who have a form of reproductive cancer, endometriosis, or uterine fibroids should not taken wild yam. This herb can interact with medications that contain estrogen, such as menopausal hormone replacement therapy.

How to Consume Wild Yam

Quick Facts (How to Consume)
  • Edible partsRoot
  • TasteBitter

Because of its nutritional content, wild yam was once used in culinary dishes; however, due the bitter flavor of the roots, this form of consumption has faded in favor of tastier, domesticated yams. Nowadays, wild yam is used mainly as a medicinal herb. It is traditionally consumed in herbal preparations and its active compound, diosgenin, is also available in a variety of over-the-counter products and prescribed drugs for the treatment of hormonal imbalances and menopause. 

Remedies

Main preparations: Capsules, liquid extract, cream

  • Capsules. This supplemental form of wild yam is taken to stimulate female fertility, as well as for the relief of premenstrual syndrome (PMS) and menopause symptoms.

  • Liquid extract. This herbal preparation provides a higher concentration of diosgenin, allowing for better and faster absorption of wild yam's for soothing PMS symptoms and protecting liver function.

  • Cream. The extracts of wild yam can be also absorbed through the skin when applied topically, in the form of a body cream, gently releasing their hormone balancing compounds.

Buying

Quick Facts (Buying)
  • Where to buySpecialized health stores, Online herb stores

Dried Wild Yam

Dried wild yam is the most common presentation in which it can be purchased, but it remains uncommon in most supermarkets. Instead, it tends to be sold through specialized health stores or online retailers. The dried roots can be purchased and consumed, and teabags can also be found.

Wild Yam Supplements

Wild yam supplements are mainly found in specialized health stores. In addition, there is a wide variety of wild yam supplement choices available through online retailers. Wild yam is most widely found as a topical cream. Potential buyers should be careful when selecting to take wild yam supplements, as wild yam is ineffective unless the featured compound, diosgenin, has been modified into an active form of progesterone. The human body cannot convert diosgenin into progesterone or estrogen.

Growing

Quick Facts (Growing)
  • Life cyclePerennial
  • Harvested partsRoots
  • Light requirementsPartial shade
  • Soil pH6.1 – 6.5 (Slightly acidic), 6.6 – 7.3 (Neutral), 7.4 – 7.8 (Slightly alkaline)
  • Growing habitatTemperate climates

Wild yam is typically found in either moist open woods, within thickets, or growing along roadsides. It is widely distributed in North America, particularly in the central and southern regions of the United States.

Growing Guidelines

  • Wild yam seeds should be planted in a partly shaded spot, with well-drained, moist soil.

  • A pH of 6.0 - 8.0. is ideal for growing wild yam plants.

  • Seedlings are sensitive to temperature changes, so it is best to grow them in a nursery or in a protected, enclosed area.

  • Germination can be expected up to three weeks after sowing the seeds.

  • The top inch (2.5 cm) of soil should be frequently watered, since this plant is highly sensitive to drought.

Additional Information

Quick Facts (Additional Information)
  • Other usesCosmetics

Plant Biology

The wild yam plant has heart-shaped leaves, and can grow up to 15 feet (4.5 m) high. The underground stem or rhizome is the most valuable part of the plant. Wild yam produces three-sided fruits, which contain winged seeds that spread by wind.

  • Classification

    Wild yam is a member of the Dioscoreaceae family, which contains about 750 species of flowering plants, with commercially produced yams being the best-known species.

    Wild yam is also a member of the Dioscorea genus, contains about 600 species spread throughout tropical and warm temperate regions of the world. Yams are this genus's most economically important crop.

  • Varieties and Subspecies of Wild Yam

    No subspecies of wild yam have been identified and no cultivars have been developed to date. Some taxonomists consider wild yam to have one variety, D. villosa var. hirticaulis. Today, however, this is more widely accepted as a synonym for Dioscorea villosa.

Historical Information

The importance of wild yam throughout history dates back to Native American cultures, where it was valued for its nutritional content and medicinal benefits.

By the 18th century, wild yams were introduced to European settlers, who saw it used in local herbal remedies, and occasionally used it as a food crop. In the 1950s, scientific studies were done on the tuber of wild yam, revealing its active compounds and mechanisms of action.

Economic Data

The main economic importance of wild yam lies in its medicinal value, as it has found use as an ingredient in some pharmaceuticals. The United States produces the largest amount of wild yam per year. Worldwide yam production as a whole rests at 48.7 million tons annually.

Other Uses

Wild yam can be found as an ingredient in cosmetics, especially body lotions, moisturizers, and butters.


Bibliography