Licorice Root Extract Products



Licorice
 

Licorice Introduction

Licorice is a woody-stemmed perennial botanical. It can grow to heights of six feet, with dark oval leaves and flowers that range in color from cream to mauve. Licorice grows wild in Southwest Asia and bordering Southeast Europe. It is also cultivated for various commercial uses all over the world. When the plant reaches three to four years of age, the roots are harvested and divided. The harvested sources make their way to commercial production, while the divided remains are once again planted for continued cultivation. [1]

Licorice is one of the most widely used botanical medicines today. It is also well known for its use in the confectionary business, due to its sweetening ability. Licorice is believed to be 50 times sweeter than sugar and can be found in a wide variety of popular candies and chews. This sweetening ability also makes it a welcome addition to many herbal preparations.

Licorice has a vast history. Its origins date back to ancient Egyptian and Greek civilizations. In fact, its nickname is derived from the Greek word Glycyrrhiza, meaning ‘sweet root.’ [2] Licorice has also been well received by many traditional societies as a healing herb; including Chinese, Kampo (Japanese), and Ayurvedic medicine. Traditional uses for licorice include; cough, consumption (tuberculosis), bronchitis, asthma, canker sores, irritated mucous membranes, digestive ailments, relaxant, constipation, and as a general tonic, used to tonify the life energy.

In the 1950-1960’s licorice gained notoriety for its use in peptic ulcer disease. It was well researched and results confirmed that licorice could actually assist in the healing of peptic ulcers. A pharmaceutical drug, carbenoxolone, was manufactured based on licorice’s efficacy and widely used to treat ulcers. However, the widespread use of licorice in the non-traditional dosages found in this drug resulted in an increased number of patient reported side effects. These adverse reactions were thought to be caused by naturally-occurring compounds found in licorice root; namely glycyrrhizin.

To combat the side effects of glycyrrhizin, a new herbal preparation was developed without the inclusion of this harmful component, called Deglycyrrhizinated licorice (DGL). This drug could be safely used to treat peptic ulcers, without the side effects caused by glycyrrhizin.

Besides being anti-ulcer, licorice also possesses other properties, including:

  • anti-inflammatory
  • anti-viral
  • hepatoprotective
  • anti-microbial
  • mucoprotective
  • demulcent
  • expectorant
  • anticariogenic
  • adrenal tonic
  • phytoestrogen, or estrogen receptor binding action
  • anti-oxidant

The main constituents in licorice are the triterpenoid saponins - glycyrrhizin at concentrations of 2 - 6% in the root. It also contains glycyrrhetinic acid (a metabolite of glycyrrhizin) flavonoids, chalcones, isoflavones, and sterols. The Isoflavones formononetin and glabridin interact with estrogen receptors. [3] Other flavonoids give licorice its purported anti-oxidant action due to the ability of these substances to quench free radicals and decrease oxidation. Several constituents (i.e. licorilcidin, glycyrin, glycyrol, and glycycoumarin) have also been shown to exhibit antibacterial activity. [4]

Licorice has adrenal tonifying action, as it inhibits the breakdown of cortisol. This action supports cortisol by increasing its effect on specifically designated tissues. Licorice also has produces similar inhibitory effects on other steroid hormones such as Prednisone; taken as a pharmaceutical prescription for many conditions. Licorice’s mild anti-inflammatory effects are thought to be due to its relationship with cortisol, since cortisol is anti-inflammatory in nature. However, there is still some confusion regarding licorice’s anti-inflammatory mechanism. [5]

Licorice may also produce mild aldosterone-like effects, which are responsible for the majority of the side effects produced by licorice. [6] This effect causes a decrease of potassium within the body and an increase in water and sodium retention; increasing the risks for the onset of high blood pressure and edema. On the other hand, this mild aldosterone activity could be helpful for individuals who have low blood pressure, or high potassium.

Licorice Food Sources

Parts Used

Root

Licorice Uses

Licorice is considered an effective treatment for peptic ulcers. Studies have shown that the many constituents found within the root can actually heal the ulcer, while exerting a protective effect on the lining of the stomach to prevent possible recurrence. It is also been deemed effective for duodenal ulcers, but is not as widely accepted as a therapeutic alternative. It also possesses the ability to reduce the secretion of acid by the stomach. However, the extent of this action is mild, and not as potent as acid blocking drugs, like Cimetidine. DGL (Deglycyrrhizinated licorice) is also effective against peptic and duodenal ulcers, without the side effects. [7]

Licorice is hepatoprotective and an excellent treatment for Hepatitis C. Individuals with Hepatitis C, a viral disease, have an increased risk of developing liver cirrhosis and hepatocellular carcinoma. Licorice may thwart the development of cancer of the liver in patients with Hepatitis C. [8-9] It is also effective at lowering the liver enzymes such as ALT and AST, which are typically elevated in these persons due to inflammation in the liver. [10] By decreasing the immune response against liver cells, licorice may provide further assistance concerning the immunological functioning of Hepatitis C patients.

A certain population of individuals do not respond to interferon, a conventional treatment for Hepatitis C. In these individuals, licorice is often employed long term as a preventative agent against the development of hepatocellular carcinoma. [11]

  • Licorice is also an effective treatment for dyspepsia, or upset stomach. [12] It can decrease the common symptoms of abdominal pain, nausea, and loss of appetite. It may also reduce acid reflux.
  • Licorice can be used topically for skin and mucous membrane conditions. It can also be applied inside of the mouth and lip region to treat canker sores. Licorice has also been used to treat other condiitons of the skin, including atopic dermatitis, or eczema. Licorice has been proven to reduce the redness, edema, and itching associated with an eczema outbreak. [13]
  • Chewable licorice or licorice gel applied to the teeth is anti-plaque and can be used to prevent cavities. Licorice is more effective at preventing cavities when it is not used in a candy chew with added sugars. [14]
  • Licorice can be used in the treatment of the common cold, bronchitis, and other infections of the upper respiratory system. It can be helpful as an expectorant, helping to reduce the amount of mucous formed and also to assist in mucous break-down. [15] Additionally, licorice’s antibacterial activity has been shown to combat several common pathogens known to cause upper respiratory infections; these include Strep pyogenes, H. influenza, and Moraxella catarrhalis. [16] Because of its many success in vitro, licorice has even been used against the SARS virus; though the majority of clinical studies refuse to support this application. [17]
  • Licorice may protect against the development of atherosclerosis. [18] Its antioxidant action prevents the oxidation of LDL, the bad cholesterol. Oxidized LDL is implicated as one of the primary steps in the development of atherosclerosis, increasing the chances of heart attack and stroke.
  • Finally licorice may be helpful for individuals with obesity. It may speed the loss of fat via cortisol signaling at the fat cell. Cortisol is increased in the blood of those taking licorice due to decreased breakdown. Cortisol increases metabolism in the fat cells, increasing weight loss.[19]

Licorice Dosages

Licorice can be taken in the form of a tea, tincture, or solid extract. It can also be applied topically in gel or cream forms. The following are excepted (safe) dosages for licorice.

  • Tea - 1-2 teaspoons of dried root per cup of water, boiled 10-15 minutes; drank 1 - 3 times daily
  • Tincture - 2-4 ml of 1:4 tincture, up to 3 times a day
  • Solid Extract - 2 - 6 ml per day of a 1:1 preparation
  • Topically - gel, cream, or mouthwash with 2% glycyrrhizin; as needed
  • Capsule - 25 - 50 mg of glycyrrhizin per day, administered in a standardized dose

It is recommended that licorice not be consumed for more than 6-8 weeks with out the guidance of a licensed health care provider, as there is potential for serious side effects to occur (e.g. high blood pressure). [20]

Licorice Toxicities and Contrainindications

Licorice can cause high blood pressure, water retention, sodium retention, and low potassium. [21] These effects are due to the stimulation of aldosterone and the adrenal gland. Excessive doses taken over the long term can lead to congestive heart failure, myopathy (muscle disease), and rhabdomyolyis (muscle cell death and breakdown). [22]

The hypertensive effects of licorice are more pronounced in individuals who already have high blood pressure, especially women. Licorice should be avoided in people who have high blood pressure. [23]

  • Licorice is contraindicated in people with high blood pressure, liver disease, low potassium, kidney disease, congestive heart failure, and gallbladder disease. [24]
  • Women who are pregnant can consume small doses of licorice for short term, but should not take high doses or use licorice long term. [25]
  • Licorice has some estrogen receptor activity and may interfere with birth control pills. [26]
  • Licorice may potentiate the potassium losing effects of several diuretics used to treat high blood pressure and congestive heart failure; therefore it should be avoided if you are taking diuretics. [27]
  • Licorice may cause an increase in the amount of prednisone in the blood in individuals who are taking prednisone. This can cause serious side effects and those taking prednisone should notify their doctor before beginning treatment with any licorice-containing supplement. [28]

References

1. Chevallier A. Encyclopedia of Herbal Medicine, 2nd Ed., 2000. Dorling Kindersley; New York: 103.

2. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.

3. Tamir S et al. Estrogen-like activity of glabrene and other constituents isolated from licorice root. J Steroid Biochem Mol Biol. 2001 Sep; 78(3): 291-298.

4. Tanaka Y, Kikuzaki H, Fukuda S, Nakatani N. Antibacterial compounds of licorice against upper airway respiratory tract pathogens. J Nutri Sci Vitaminol. (Tokyo) 2001 Jun; 47(3): 270-273.

5. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.

6. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.

7. Larkworthy W, Holgate PF. DGL in the treatment of chronic duodenal ulcer: a retrospective endoscopic survey of 32 patients. Practitioner. 1975 Dec; 215(1290): 787-792.

8. Kumada H. Long term treatment of chronic Hepatitis C with glycyrrhizin [stronger neo-minophagen C (SNMC)] for preventing liver cirrhosis and hepatocellular carcinoma. Oncology. 2002; 62(Suppl1): 94-100.

9. Chayama K. Management of hepatitis C and prevention of hepatocellular carcinoma. J Gastroenterol. 2002; 37(Suppl13): 69-73.

10. Bean P. The use of alternative medicine in the treatment of Hepatitis C. Am Clin Lab. 2002 May; 21(4): 19-21.

11. Kumada H. Long term treatment of chronic Hepatitis C with glycyrrhizin [stronger neo-minophagen C (SNMC)] for preventing liver cirrhosis and hepatocellular carcinoma. Oncology. 2002; 62(Suppl1): 94-100.

12. Madisch A, Holtmann G, Mayr G, Vinson B, Hotz J. Treatment of functional dyspepsia with herbal preparation. A double blind randomized placebo-controlled multi-center trial. Digestion. 2004; 69(1): 45-52.

13. Saeedi M, Morteza-Semnani K, Ghoreishi MR. The treatment of atopic dermatitis with licorice gel. J Dermatolog Treat. 2003 Sep; 14(3): 153-157.

14. Steinberg D et al. The anticariogenic activity of glycyrrhizin: preliminary clinical trials. Is J Sci. 1989 Oct; 2(3): 153-157.

15. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.

16. Tanaka Y, Kikuzaki H, Fukuda S, Nakatani N. Antibacterial compounds of licorice against upper airway respiratory tract pathogens. J Nutri Sci Vitaminol. (Tokyo) 2001 Jun; 47(3): 270-273.

17. Cinatl J e al. Glycyrrhizin: an active component of licorice roots, and replication of SARS-associated corona virus. Lancet. 2003 Jun 14; 361(9374): 2045-2046.

18. Belinky PA, Aviram M. Antioxidant constituents from licorice roots: isolation, structure elucidation, and antioxidative capacity towards LDL oxidation. Free Radic Biol Med. 1997; 23(2): 302-313.

19. Armanini D et al. J Endocrinol Invest. 2003 Jul; 26(7): 646-650.

20. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.

21. Epstein MT, Espiner EA, Donald RA, Hughes H. Effects of eating liquorice on the rennin-angiotensin aldosterone axis in normal subjects. Br Med J. 1977 Feb 19; 1(6059): 488-490.

22. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.

23. Sigurjonsdottir HA et al. Subjects with essential hypertension are more sensitive to inhibition of 11-beta HSD by liquorice. J Hum Hypertens. 2003 Feb; 17(2): 125-131.

24. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.

25. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.

26. Tamir S et al. Estrogen-like activity of glabrene and other constituents isolated from licorice root. J Steroid Biochem Mol Biol. 2001 Sep; 78(3): 291-298.

27. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.

28. Mills S, Bone K. Principles and Practice of Phytotherapy, 2000. Churchill Livingstone, London: 465-478.