Glycyrrhiza glabra is a perennial temperate zone shrub, native of the Mediterranean and as far as Iran and southern Russia. It is certainly one of the most extensively used and scientifically investigated herbal medicines, its use going back several thousand years. Its major active root ingredient is glycyrrhizin, which appears to be hydrolyzed by intestinal flora to yield the backbone molecule glycyrrhetinic acid and a sugar molecule. Other constituents are isoflavonoids like isoflavonol, kumatakenin, licoricone, glabrol, etc, coumarins like umbelliferone, herniarin, etc, chalcones, triterpenoid saponins, phytosterols, lignins, amino acids, amines, gums and volatile oils. However, despite its multiple benefits, licorice through glycyrrhetinic acid can act like the hormone ACTH, causing sodium and water retention and potassium depletion. Excess licorice intake can lead to the classic symptoms of hypertension with increased blood pressure, edema, potassium loss and muscular weakness. For this reason glycyrrhizin is taken out of some licorice preparations and this deglycyrrhizinated form (DGL) is often used.

  • Adrenal tonic. The herb has been used against adrenal exhaustion, and evidence shows that it can counteract the effects of adrenal hormone insufficiency. The glycoside glycyrrhizin has a similar structure and activity as the adrenal steroids. Significantly, licorice not only has cortisol-like effects, but it has also been shown to counteract some of the side effects of long term use of corticosteroid drugs.
  • Anti-allergic. The cortisol-like effect of licorice and the inhibition of certain series 1 prostaglandins and histamine, constitute a substantial anti-allergic potential.
  • Anti-canker sores. Reccurent canker sores are common. DGL tablets may be effective in promoting healing. In one study using a DGL solution as a mouthwash, three quarters of the patients experienced 50-75 percent improvement on the first day and complete healing by the third. DGL tablets may work even better.
  • Anti-inflammatory. Licorice has an anti-inflammatory activity similar to cortisone. In addition, it seems to inhibit phospholipase A2, an enzyme responsible for the manufacture of the inflammatory series 1 prostaglandins and leucotrienes.
  • Anti-ulcer. The deglycyrrhizinated form (DGL) has been clinically proven to treat ulcers in the upper digestive tract, because of its ability to stimulate the normal defence mechanisms that prevent the formation of ulcers. That is, DGL improves the integrity of the mucosal surfaces of the intestinal tract, extends the life span of the intestinal cells, and increases the blood supply to the intestinal mucosa. Chewing is better than swallowing the DGL tablets.
  • Anti-viral. The licorice compounds glycyrrhizin and glycyrrhetinic acid enhance the activity of interferon, the body’s principal anti-viral natural compound. Interferon binds to cell surfaces and stimulates the formation of intracellular proteins, which block viral DNA. Thus licorice has shown beneficial effects with the viruses of the common cold, influenza, chronic fatigue syndrome, and herpes infections.
  • Detoxifier. Scientific evidence has shown that licorice possesses certain liver-supportive properties, which seem to justify the herb’s traditional use in Chinese medicine as a powerful detoxifier.
  • Female hormonal tonic. Licorice contains phytoestrogens often used to modify the estrogen activity of the body. When the levels of natural estrogen are high, the herb’s comparatively weaker phytoestrogens can occupy receptors that would be otherwise occupied by the more powerful body hormones. When the natural estrogen levels are low, the phytoestrogens can exert a mild positive effect if used in larger amounts. However, research shows that the actual process may be more complex, with isoflavones potentiating estrogen action, and glycyrrhetinic acid antagonizing this action. Research also suggests that licorice may enhance progesterone activity, by slowing down its destruction in the liver.
  • Hepatitis B reliever. Hepatitis B is one of the most difficult infections the body has to face and resolve. For this purpose, Japanese health workers use a preparation called Stronger Neominophagen C (SNMC), consisting of glycyrrhizin, glycine to prevent the hypertensive effects of licorice, and cysteine to assist the liver in the detoxification reactions. SNMC improves liver function, and reduces blood levels of liver enzymes signifying liver damage. Approximately 40 percent of patients seem to experience complete remission.

Caution: Chronic high doses of licorice may cause the above described hypertension symptoms. There are two ways of avoiding that. One is potassium supplementation; the other and simpler is using deglycyrrhizinated licorice or DGL.