Licorice is an herb, derived from the root of Glycyrrhiza glabra, a legume indigenous to the Mediterranean and parts of Asia.
Licorice is not related to anise or fennel, although they are both sources for similar flavouring compounds. The compound responsible for sweetness is glycyrrhizin, a compound 50 times sweeter than sucrose. Tiny amounts are backed with aniseed oil to create licorice, the candy.
Licorice has and still is used to treat a diverse group of diseases. Traditional practitioners recommended to thei patients that they chew on the root of the plant.
Chinese medical texts describe licorice as a harmonizing agent used to improve the digestive system, replenish qi and relieve pain. Ayurvedic texts speak of releaving ‘vata’ and ‘kapha’. See the article from wikipedia below. These therapies reflects the diversity of the compounds in the plant and the many ways they can be used by the body.
Licorice’s library of compounds protect hepatic functions and aids digestion. It is also used as an anti-tussive and expectorant. But licorice is most valued because of its high antioxidant and anti-inflammatory activity.
Licorice may reduce the formation of arterial plaque by this anti-inflammatory effect, which is also usefull in the treatment of other chronic disorders like arthritis.
Licorice consists of the dried underground parts (rhizome and root) of the plant. One of its active components is glycyrrhizin, the calcium and potassium salts of glycyrrhizic acid, a substance 50 times sweeter than cane sugar. Other components include triterpenoid saponins, flavonoids (glabridin) and a few estrogenic substances.
The activity of licorice is based on glycyrrhizin or glycyrrhetinic acid. Its triterpenoid structure is similar to the hormones of the adrenal cortex (cortisol).
Licorice has strong anti-inflammatory and anti-arthritic activity similar in effect to hydrocortisone, albeit at a reduced intensity.
Licorice stimulates the adrenal cortex and mineralcorticoid secretion. It also inhibits aldosterone breakdown by the liver.
Licorice mimics the activity of ACTH causing an aldosterone-like retention of water and sodium. The combination of increasing plasma sodium ion levels and retaing water raises blood pressure.
Licorice reduces gastric secretion and help forms a thick mucus lining to protect the stomach. It is therefore useful in treating peptic ulcers and inflammatory disorders of the digestive system. Biogastrone is a licorice based drug used to treat peptic ulcers. Licorice has significant anti-inflammatory and anti-arthritic action similar to corticosteroid hormones.
Its cortisol-like effect is probably based on an inhibition of enzymatic breakdown of cortisol by the liver. Glycyrrhizin binds to glucocorticoid receptors and inhibits the formation of prostaglandins and leukotrienes.
Glabridin protects the LDL molecule from oxidative damage thereby preventing plaque.
Licorice acts as a classic saponin-containing remedy, in the same group as ginseng. Licorice restores balance to the functions it affects and is considered more soothing and moistening relative to ginseng. Underlying all harmony remedies is their ability to aid the body to resist stress. The saponins resemble the steroid nucleus and therefore mimic the activity and prolong the life of the natural hormones produced by the adrenal cortex.
Glycyrrhizin induces interferon activation. Interferon is an antiviral compound that blocks viral DNA and causes an activation of macrophages. It also reduces capillary permeability slowing the inflammatory response. Licorice is a hepatic-protective agent that prevents free radical formation and its consequential oxidative damage.
Licorice improves the body’s ability to withstand stress. It is recommended to spped recovery following intense exercise. In addition to its anti-inflammatory activity, licorice causes an anti-diuretic effect. Excessive use of licorice can lead to fluid and sodium retention and a consequential increase in blood pressure. Licorice is often used by athletes withdrawing from steroids. Steroids suppress the adrenal cortex through feedback inhibition. Licorice reduces the breakdown of existing hormones and provides an ACTH-like approach in stimulating the adrenal cortex to produce more corticosteroids, such as cortisol.
In Ayurveda (traditional Indian medicine) and traditional Chinese medicine, liquorice(मुलेठी, 甘草) is commonly used in herbal formulae to "harmonize" the other ingredients in the formula and to carry the formula to the twelve "regular meridians" and to relieve a spasmodic cough.
In herbalism it is used in the Hoxsey anti-cancer formula, and is a considered adaptogen which helps reregulate the hypothalamic-pituitary-adrenal axis. It can also be used for auto-immune conditions including lupus, scleroderma, rheumatoid arthritis and animal dander allergies.
Glycyrrhizin from Glycyrrhiza root has been shown to modulate airway constriction, lung inflammation and infiltration of eosinophils in bronchial areas by stimulating CD4 and CD8 immune cell function.