Chinese Yam (Huai Shan)

Common Yam Rhizome (shan yao, 山药), more commonly known as Chinese Yam or Huai Shan (淮山), refers to the roots of Dioscorea opposita, a vine plant in the family Dioscoreaceae. 

Originally called shu yu in classical Chinese texts, Huai Shan has its name changed when similar components in the names of two Tang and Song dynasty emperors rendered the characters shu and yu taboo for common use. Shu yu means “gigantic root that nourishes reserves”, and the herb was said to be ‘indicated for all states of deficiency’ in the 1800-year-old clinical primer Jingui yaolüe.

In China, Chinese Yam is mainly produced in Henan, Hunan and other regions that are South of the Yangtze River. Traditionally, Chinese Yams from Henan are believed to have the highest medicinal properties and nutritional value. Perhaps the blandest of all Chinese herbs, Chinese Yam is treasured in Chinese cuisine as a food-grade qi tonic that is included in everyday soups and gruels. In particular, it has a reputation of being a safe and effective tonic for children suffering from weak digestion or malnutrition.

In Traditional Chinese Medicine (TCM), Chinese Yam falls under the category of ‘Tonic herbs for Qi Deficiency’. Such herbs are used for patterns of Deficiency to replenish one’s ‘Four Treasures’ (qi, blood, yin, yang). Neutral in nature, Chinese Yam does not affect the yin-yang balance in your body. Sweet in taste, the herb can slow down acute reactions, detoxify the body, and has a tonic effect by replenishing qi and blood. In particular, the herb targets the Kidneys, the Lungs and the Spleen.

Traditional Chinese Medicine (TCM) shows that Chinese Yam has the following health benefits.

Chinese Yam can tonify qi in the Spleen. The herb is indicated for symptoms such as irritable bowel syndrome, poor appetite with loose stools and diarrhea caused by Spleen Qi Deficiency and Yin Deficiency. It can be consumed directly as food or used as part of a herbal formula. For serious cases of Qi Deficiency, Chinese Yam is commonly combined with other qi and Spleen tonics to enhance its effects.

Chinese Yam can tonify qi and yin in the Lungs as well. For cough with little sputum or no sputum, shortness of breath, dyspnea and spontaneous sweating caused by Lung Qi and Yin Deficiency, Chinese Yam is frequently combined with herbs that can tonify qi, nourish yin, moisten Lungs or relieve cough. 

Chinese Yam can also tonify qi and yin in the Kidneys. A common ingredient in many Kidney-tonifying herbal formulas, Chinese Yam can address symptoms such as soreness and weakness of lumbar and knees, frequent urination, enuresis, seminal emission, abnormal vaginal discharge and premature ejaculation. In addition, Chinese Yam can treat diabetes caused by Qi and Yin Deficiency. 

Modern studies have discovered that Chinese Yam may help to lower cholesterol levels. An animal study demonstrated that the mucilage in Chinese Yam may reduce cholesterol absorption from the gut. However, more research is required to confirm the effects of Chinese Yam on cholesterol levels in the human body. Other studies have found that polysaccharides in Chinese Yam helps to lower blood sugar levels.

Rich in dietary fibre and prebiotics, Chinese Yam may help to maintain a healthy digestive system. The herb can help to keep the digestive system clean and free of harmful bacteria. Also, Chinese Yam may help with weight loss by regulating appetite and metabolism.

A natural source of antioxidants and anti-inflammatory properties, Chinese Yam may help to reduce pain and swelling associated with cancer and to improve cancer symptoms. Chinese Yam has also been shown to fight nausea and vomiting that are associated with cancer treatments.

Containing mucilage, Chinese Yam can soften the skin and manage skin disorders. It can also promote wound healing and soothe rashes and burns. If ground or grated and spread on the skin, the herb may heal cuts, scrapes and other similar conditions.

To prepare fresh Chinese Yam for consumption, simply wash and peel its skin, then cut it into cubes or slices for cooking. Fresh Chinese Yam is most commonly used in rice, porridge and vegetable soup. 

For dried Chinese Yam, it is commonly used to cook with other herbs to make herbal soup. When cooking the herb, it is better to soak it for about an hour so that it absorbs as much water as possible. If possible, eat the Chinese Yam together with the soup for the best tonic effect.

Do take precautions when you are washing and cutting Chinese Yam as it may make the skin that it comes into contact with itchy. Try to wear gloves when cutting Chinese yam to avoid experiencing itchy sensations afterwards.

Chinese Yam should be used with caution by individuals experiencing Excess Heat or Dampness, especially Dampness in the abdomen.

Also, Chinese Yam contains estrogen. Over-consuming Chinese Yam may over-stimulate hormones and cause symptoms such as endometrial hyperplasia, menstrual disorder, prolonged menstrual period and menstrual pain.

It is best to not consume Chinese Yam raw or together with Euphorbia Kansui (gan sui) or Carp. These combinations may cause adverse reactions such as diarrhea, vomiting, nausea and abdominal pain.

Other allergic reactions to Chinese Yam include skin irritation, hives and difficulty breathing.

We strongly encourage you to consult your healthcare provider before deciding to add Chinese Yam to your healthcare routine!

 

Here is a summary for Chinese Yam (Huai Shan):

• Herb name (Chinese): 淮山 or 山药
• Herb name (Pin Yin): huai shan or shan yao
• Herb name (English): Common Yam Rhizome
• Herb name (Botanical): Rhizoma Dioscoreae
• Origin of species: Dioscorea opposita Thunb.
• Part(s) of herb used: Rhizome
• Geo-specific habitat(s): Henan, Hunan, Jiangnan
• Taste(s) & Properties: Sweet; Neutral; Administrates the Spleen, Lung and Kidney Meridians
• Actions: Boosts and improves digestive and respiratory functions; Relieves symptoms related to weak knees, sore lower back, frequent night urination, premature ejaculation and excessive vaginal discharge; Eases constant thirst due to chronic diseases such as diabetes

Epping, J., & Laibach, N. (2020). An underutilized orphan tuber crop—Chinese yam: A review. Planta, 252(4), 1-19. [Accessed on 11th December 2022]

Liu, Y., Li, H., Fan, Y., Man, S., Liu, Z., Gao, W., & Wang, T. (2016). Antioxidant and antitumor activities of the extracts from Chinese yam (Dioscorea opposite Thunb.) flesh and peel and the effective compounds. Journal of Food Science, 81(6), H1553-H1564.[Accessed on 11th December 2022]

Zhang, N., Liang, T., Jin, Q., Shen, C., Zhang, Y., & Jing, P. (2019). Chinese yam (Dioscorea opposita Thunb.) alleviates antibiotic-associated diarrhea, modifies intestinal microbiota, and increases the level of short-chain fatty acids in mice. Food Research International, 122, 191-198.[Accessed on 11th December 2022]