Shān Yào (山药) — Chinese Yam (Dioscorea)
On this page
- Overview
- Properties
- Actions and indications
- Key formulas
- Modern research
- Cautions and contraindications
- Treatment at my clinic
1. Overview
Shān Yào (山药) — Dioscorea opposita / polystachya — is known in English as Chinese yam / Dioscorea. It belongs to the category of Qi tonics in the Chinese Materia Medica and is one of the most important and widely prescribed herbs in traditional Chinese medicine (TCM). It is used in Chinese herbal medicine both as a component of classical herbal formulas and as a significant individual herb in tailored prescriptions.
I prescribe Shān Yào as part of bespoke herbal formulas from pharmaceutical-grade granules sourced from Sun Ten in Taiwan — independently tested to the highest international quality and safety standards. Herbs are never prescribed individually outside a properly balanced formula; they are always combined with other herbs selected to match the patient’s individual TCM pattern. Online consultations are available for patients who cannot attend my clinic in person.
2. Properties
| Pinyin name | Shān Yào |
|---|---|
| Chinese characters | 山药 |
| Latin name | Dioscorea opposita / polystachya |
| English name | Chinese yam / Dioscorea |
| Nature | Neutral |
| Flavour | Sweet |
| Channels entered | Lung, Spleen, Kidney |
| Category | Qi tonics |
3. Actions and indications
Principal actions
- Tonifies the Spleen and Stomach Qi and Yin simultaneously
- Tonifies the Lung Qi and Yin
- Tonifies the Kidney and astringes Jing
- Generates Body Fluids
- Absorbs moisture and stops diarrhoea
Indications
- Spleen Qi deficiency with fatigue, poor appetite, diarrhoea and loose stools
- Spleen and Stomach Yin deficiency with dry mouth and poor appetite
- Lung Qi and Yin deficiency with chronic cough and wheezing
- Kidney Qi deficiency with spermatorrhoea, urinary frequency and vaginal discharge
- Wasting and thirsting disorder from combined Spleen, Lung and Kidney Qi and Yin deficiency
- PCOS — improves insulin sensitivity; nourishes Spleen Yin and counterbalances Yang tonics
4. Key formulas containing Shān Yào
Shān Yào is an ingredient in many classical formulas. The following are among the most important:
See the full Chinese herbal medicine formula directory for detailed information on all 70 classical formulas.
5. Modern research
Dioscorea opposita (Shan Yao) has been the subject of significant modern research, particularly in diabetes and metabolic syndrome. Key bioactive constituents include diosgenin (a steroidal saponin), allantoin, polysaccharides and DHEA precursors. Research confirms antidiabetic effects (improving insulin sensitivity and reducing blood glucose), immunomodulatory properties, anti-ageing effects and beneficial effects on gut microbiota. Diosgenin is a precursor used industrially in the synthesis of steroidal hormones including DHEA and progesterone, though direct conversion does not occur in the body. Shan Yao polysaccharides have been shown to improve follicular development and ovarian function in animal models, supporting its fertility applications.
6. Cautions and contraindications
Generally very safe and often used as a food. Use with caution in patients with excess Dampness and stagnation, as the sweet, astringent nature may worsen these conditions.
Important: Chinese herbs should always be prescribed by a fully qualified herbalist who is a member of the Register of Chinese Herbal Medicine (RCHM). Never self-prescribe or self-administer Chinese herbs without professional guidance. Dr (TCM) Attilio D’Alberto is a member of the RCHM and the British Acupuncture Council with over 25 years of clinical experience.
7. Treatment at my clinic
I prescribe Shān Yào as part of tailored herbal formulas for a range of conditions including PCOS, Digestive disorders, Chronic fatigue syndrome. Every prescription is individually formulated following a full TCM assessment and adjusted throughout treatment as the pattern responds.
I see patients in person at my clinic in Wokingham, Berkshire. Online Chinese herbal medicine consultations are available for patients throughout the UK and internationally, with herbs dispensed by post. Visit the prices page for consultation fees.
Return to the Chinese herb directory or the Chinese herbal medicine main page.
