Use of liquorice (Gan Cao) in TCM
Please note that you should never self-prescribe TCM ingredients. A TCM ingredient is almost never eaten on its own but as part of a formula containing several ingredients that act together. Please consult a professional TCM practitioner, they will be best able to guide you.
Preparation: Remove impurities, wash, soak in water, cut thick slices, dry.
Dosage: 2 - 10g
Main actions according to TCM*: Tonifies the Basal Qi and nourishes the Spleen Qi. Clears Heat and dispels toxicity. Moistens the Lungsexpel phlegm and stop coughing. Relieves spasms and alleviates pain. Harmonizes and moderates the effects of other herbs.
Primary conditions or symptoms for which liquorice may be prescribed by TCM doctors*:
Contraindications*: Licorice should not be used when there is Excess Dampness, nausea or vomiting and generally should be used with caution by those who tend to retain water.
People with heart conditions or high blood pressure should avoid ingesting large amounts of liquorice as it can increase blood pressure.
Prolonged use (6 weeks) of excessive doses (50g/day) can lead to pseudoaldosteronism.
Common TCM formulas in which liquorice are used*:
- For spirochete diseases such as syphilis and Lyme's disease combine liquorice with dandelions (Pu Gong Ying), smilax glabra roots (Tu Fu Ling), honeysuckle flowers (Jin Yin Hua), dittany root bark (Bai Xian Pi) and purslane (Ma Chi Xian).
- For postpartum inflammation, septicemia and/or accompanying restlessness combine liquorice with swallow-wort roots (Bai Wei), ginseng (Ren Shen) and dong quai (Dang Gui).
- For sore throat and hoarse voice combine liquorice with ningpo figwort roots (Xuan Shen), platycodon roots (Jie Geng) and greater burdock fruits (Niu Bang Zi).
- For infantile vomiting combine liquorice with amomum fruits (Sha Ren).
- For asthma or chronic bronchitis combine liquorice with ginkgo nuts (Bai Guo), ephedra (Ma Huang), perilla seeds (Zi Su Zi), coltsfoot flowers (Kuan Dong Hua), apricot seeds (Xing Ren), mulberry bark (Sang Bai Pi), baikal skullcap roots (Huang Qin) and crow-dipper rhizomes (Ban Xia).
- For Lung and Kidney Yin Deficiency associated with chronic bronchitis, asthma or chronic pharyngitis combine liquorice with lily bulbs (Bai He), prepared rehmannia (Shu Di huang), unprepared rehmannia (Di Huang), dwarf lilyturf roots (Mai Dong), white peony roots (Bai Shao), dong quai (Dang Gui), ningpo figwort roots (Xuan Shen), platycodon roots (Jie Geng) and fritillary bulbs (Chuan Bei Mu).
- For rheumatism, muscular pains and spams or lumbago combine liquorice with notopterygium roots (Qiang Huo), turmeric (Jiang Huang), milkvetch roots (Huang Qi), dong quai (Dang Gui), red peony roots (Chi Shao), saposhnikovia roots (Fang Feng), fresh ginger (Sheng Jiang) and jujube dates (Da Zao).
- For general Qi tonification combine liquorice with ginseng (Ren Shen), atractylodes rhizomes (Bai Shu) and poria-cocos mushrooms (Fu Ling).
- For rheumatic and arthritic conditions combine liquorice with job's tears (Yi Yi Ren), ephedra (Ma Huang) and apricot seeds (Xing Ren).
- For coronary heart disease, rheumatic heart disease, myocarditis, arrhythmia, hyperthyroidism or neurasthenia combine liquorice with jujube dates (Da Zao), ginseng (Ren Shen), unprepared rehmannia (Di Huang), dwarf lilyturf roots (Mai Dong), hemp seeds (Huo Ma Ren), cinnamon twigs (Gui Zhi) and fresh ginger (Sheng Jiang).
- For harmonizing Internal and External symptoms, Cold and Heat, Excess and Deficiency and treating associated symptoms (common cold, influenza, pneumonia, indigestion, nervous exhaustion, etc.) combine liquorice with jujube dates (Da Zao), bupleurum roots (Chai Hu), crow-dipper rhizomes (Ban Xia), white peony roots (Bai Shao), baikal skullcap roots (Huang Qin), ginseng (Ren Shen), cinnamon twigs (Gui Zhi) and fresh ginger (Sheng Jiang).
- For Deficient Wind-Cold Exterior condition with symptoms such as colds, flu, fever, headache, intolerance to Wind and Cold or spontaneous perspiration combine liquorice with cinnamon twigs (Gui Zhi), white peony roots (Bai Shao), fresh ginger (Sheng Jiang) and jujube dates (Da Zao).
- For conditions such as anemia, weakness, tiredness, irregular menses caused by exhaustion or postpartum recovery combine liquorice with ginseng (Ren Shen), atractylodes rhizomes (Bai Shu), poria-cocos mushrooms (Fu Ling), dong quai (Dang Gui), szechuan lovage roots (Chuan Xiong), prepared rehmannia (Shu Di huang), white peony roots (Bai Shao), fresh ginger (Sheng Jiang) and jujube dates (Da Zao).
- For severe colds, flu or upper respiratory tract infections combine liquorice with honeysuckle flowers (Jin Yin Hua), forsythia fruits (Lian Qiao), platycodon roots (Jie Geng), greater burdock fruits (Niu Bang Zi), wild mint (Bo He), fermented soybeans (Dan Dou Chi), lophatherum herbs (Dan Zhu Ye), common reed rhizomes (Lu Gen), notopterygium roots (Qiang Huo) and woad roots (Ban Lan Gen).
- For the treatment of prolapsed Qi with symptoms of chronic fatigue and weakness as a result of physical exertion or stress combine liquorice with bupleurum roots (Chai Hu), codonopsis roots (Dang Shen), atractylodes rhizomes (Bai Shu), milkvetch roots (Huang Qi), ginseng (Ren Shen), dong quai (Dang Gui), bugbane rhizomes (Sheng Ma) and tangerine peel (Chen Pi).
- For Summer-Heat with thirst, irritability and fever combine liquorice with adzuki beans (Chi Xiao Dou) and goldthread rhizomes (Huang Lian).
- For abdominal pain combine liquorice with honey (Feng Mi), white peony roots (Bai Shao), cinnamon twigs (Gui Zhi) and dried ginger (Gan Jiang).
Key TCM concepts behind liquorice (Gan Cao)'s properties
In Traditional Chinese Medicine (TCM), liquorice are plants that belong to the 'Tonic herbs for Qi Deficiency' category. Tonic herbs are used for patterns of Deficiency, when one lacks one of the 'Four Treasures' (Qi, Blood, Yin and Yang). Qi tonics are typically sweet and they tend to enter the Spleen and Lungs because these organs are most involved with the production of Qi.
Furthermore liquorice are plants that are Neutral in nature. This means that liquorice typically don't affect the balance in your body. Balance between Yin and Yang is a key health concept in TCM. Eating too many "Hot" (Yang) ingredients can lead to an imbalance whereby one has a Yang excess. The inverse is true as well: too many "Cold" (Yin) ingredients can lead to a Yin excess. The Neutral nature of liquorice means that you don't have to worry about that!
Liquorice also taste Sweet. The so-called "five elements" theory in Chinese Medicine states that the taste of TCM ingredients is a key determinant of their action in the body. Sweet ingredients like liquorice tend to slow down acute reactions and detoxify the body. They also have a tonic effect because they replenish Qi and Blood.
The tastes of ingredients in TCM also determine what organs and meridians they target. As such liquorice are thought to target the Spleen, the Stomach, the Heart and the Lung. In TCM the Spleen assists with digestion, blood coagulation and fluid metabolism in the body. The Stomach on the other hand is responsible for receiving and ripening ingested food and fluids. It is also tasked with descending the digested elements downwards to the Small Intestine. In addition to regulating blood flow, the Heart is believed to be the store of the "spirit" which basically refers to someone's vitality. In addition to performing respiration, the Lungs are thought to be a key part of the production chain for Qi and the body fluids that nourish the body.
Research on liquorice(Gan Cao)
In vivo and clinical studies have reported beneficial effects of both licorice and glycyrrhizin consumption including anti-ulcer, anti-viral, and hepatoprotective responses.1
Flavonoids extracted from Glycyrrhiza uralensis may have a potential antidepressant-like effect for chronic variable stress induced depression2
1. Isbrucker RA, Burdock GA. ( 2006). Risk and safety assessment on the consumption of Licorice root (Glycyrrhiza sp.), its extract and powder as a food ingredient, with emphasis on the pharmacology and toxicology of glycyrrhizin. Regul Toxicol Pharmacol. , 46(3):167-92. Epub 2006 Aug 1.
2.Z Zhao, W Wang, H Guo, D Zhou. (2008). Antidepressant-like effect of liquiritin from Glycyrrhiza uralensis in chronic variable stress induced depression model rats. Behavioural brain research, Elsevier
Use of liquorice (Gan Cao) as food
Liquorice are also eaten as food. It is used as an ingredient in dishes such as Liquorice creme brulee or Licorice Caramel Candy.