Dioscorea Rhizoma
Aliases：Shǔ Yù (Yam); Shān Yù (Mountain Taro); Huái Shān Yào (Huai Yam); Huái Shān Yào (Huai Yam); Yě Shān Dòu (Wild Mountain Bean); Shān Bǎn Shù (Mountain Board Herb); Jiǔ Huáng Jiāng (Nine-Yellow Ginger); Bái Yào Zǐ (White Medicinal Seed); Yě Bái Shǔ (Wild White Yam); Fó Zhǎng Shǔ (Buddha‘s Palm Yam); Yù Yán (Jade Extension); Xiū Cuì (Crisp Root); Shǔ Yù (Yam).
Shān Yào (Common Yam Rhizome) is a Chinese medicinal herb. It is a commonly used qi-tonifying medicinal material, and is the rhizome of Dioscorea opposita Thunb., a plant of the Dioscoreaceae family. Shān Yào was listed as a top-grade herb in the Shennong Bencao Jing (The Divine Farmer‘s Materia Medica) and is considered an excellent medicinal and edible substance.
Efficacy & Actions
Tonifies the spleen and nourishes the stomach; promotes fluid production and benefits the lungs; tonifies the kidneys and astringes essence.
Indications
Used for spleen deficiency with poor appetite, chronic diarrhea, fatigue and weakness, loose stools and diarrhea, lung-deficiency cough and wheezing, kidney-deficiency spermatorrhea, leukorrhea with frequent urination, and wasting-thirst disorder due to deficient heat, among other conditions.
Modern Pharmacology
Hypoglycemic effect: Has an adjunctive therapeutic effect on diabetes. Immunomodulatory effect: Enhances immune function. Antioxidant and anti-aging effects. Antitumor effect. Renal protective effect: Has therapeutic effects on kidney diseases. Improvement of gastrointestinal function. Hepatoprotective and anti-inflammatory effects. Lipid-lowering effect. Uric acid-lowering effect.
Ingredients
Polysaccharides: The main active components, with various effects including immunomodulatory, anti-aging, antitumor, and hypoglycemic activities. Saponins: Mainly steroidal saponins. Allantoin. Amino acids and proteins. Starch. Fatty acids. Polyphenols and flavonoids. Trace elements.
Usage & Dosage
Oral Administration: Decoction, the standard dosage is 15–30g; in larger doses, up to 60–250g may be used. May also be prepared in pills or powder. For nourishing yin and promoting fluid production, it should be used raw. For strengthening the spleen and stopping diarrhea, it should be stir-fried until yellow. Topical Application: Appropriate amount, mashed for external application.
Contraindications
Not suitable for patients with dampness excess with abdominal fullness or food stagnation. Contraindicated in patients with excess heat or pathogenic excess patterns. Incompatible with Gansui (Kansui Root); should not be used together with Gansui. Should not be consumed together with flour-based foods. When used together with alkaline herbs such as Hai Piao Xiao (Cuttlebone), Long Gu (Dragon Bone), Mu Li (Oyster Shell), and Wa Leng Zi (Ark Shell), the efficacy may be reduced. The saponin in yam skin or the plant alkaloids in its mucilage may cause allergic itching in a small number of people upon contact. Avoid direct contact when handling.
Selected Formulas
For spleen-deficiency diarrhea and consumptive fever (Yixue Zhongzhong Canxi Lu, Yiwei Shuyu Yin) Take 120g of raw Shanyao (Chinese yam), decoct in water to obtain two large bowls of liquid, and drink slowly as tea. For spleen deficiency with dampness exuberance (Shanyao Fuling Congee, empirical formula) Take 100g of fresh Shanyao, 15g of Fuling (Poria), and 50g of rice. Cook into congee and eat. For restlessness, insomnia, and insecurity of spleen and kidney (Shanyao Lianzi Geng, empirical formula) Take Shanyao, Lianzi (Lotus seed), and Baihe (Lily bulb). Cook together and eat.
Daily Consumption
Yam Congee (Strengthens the Spleen and Nourishes the Stomach): Take 50g of fresh yam and 200g of rice. Cook them together into a congee. Yam and Pork Rib Soup (Tonifies Qi and Benefits the Kidneys): Stew yam together with pork ribs and goji berries. Yam and Poria Powder: Stir-fry equal amounts of yam and poria, then grind into a fine powder. Take 30–50g each time, mix with water, and drink. Yam and Almond Drink: Take 100g of steamed yam, 10g of sweet apricot kernels, 200ml of milk, and a small amount of rock sugar. Blend well in a blender and consume.
Medicinal Parts
Dried rhizome.
Selection & Storage
Store in a dry container in a well-ventilated, dry place, protected from mold and insects.
