The Antiviral Effects of Liquorice
Glycyrrhiza glabra, the main species of liquorice, is a perennial herb, native to central and South-Western Asia, the Mediterranean and can be cultivated in temperate and sub-tropical regions1. The dried, processed root has been used for medicinal purposes since at least 500 BC2; the first therapeutic uses of liquorice can be traced back to ancient Egyptian, Chinese, Roman and Greek cultures3. Documented use from the middle ages mention its use against what appeared to me respiratory tract infections, such as dry cough, and to relieve the symptoms of hepatitis, suggesting that liquorice had recognised antiviral properties1, 3. Today liquorice remains one of the most widely used medicinal plants globally against a wide variety of viral illnesses. Three decades of research into the use of Glycyrrhiza throughout the ages of documented human history to identify the active compounds of the liquorice root that confer the antiviral effects, which include saponins, flavanoids, isoflavones, coumarins and stilbenoids2.
The dried liquorice root has been therapeutically used against viral infections of the respiratory system, gastrointestinal system, cardiovascular system, genital-urinary system, skin and eye1-4. It would take more than this article would allow cataloguing all the viruses and studies that have shown positive effects of liquorice supplementation, so instead some key examples are mentioned.
Viral hepatitis kills 1 million people per year and, according to global estimates, a staggering 500 million worldwide is believed to be affected by the disease, more than ten times the number affected by HIV/AIDS5. The World Health Organisation claims that "the burden of disease is truly dramatic yet viral hepatitis has been forgotten and misplaced". Measures to combat and relieve the symptoms of the disease are greatly lacking in modern society5. For the past 20 years, Glycyrrhizin, a glucoside found in the liquorice root, has been used in Japan as a treatment for chronic hepatitis1. In randomized controlled trials, in patients with viral hepatitis, intravenous administration of glycyrrhizin, resulted in a significant reduction of serum liver enzymes and caused an improvement in liver histology in comparison with placebo1.
Among adults 15 to 49, the proportion currently infected with HIV is between 0.8-1% and the deaths caused by AIDS is approximately accounts for 4% of all deaths, with 2.2 million dying from the infection, globally each year6. Dealing with HIV and preventing HIV infections are clearly global health concerns. A study by Mori et al1 in haemophilia A patients with HIV infection found that glycyrrhizin not only possesses an inhibitory effect on HIV replication, but also has interferon-inducing and natural killer-enhancing effects, factors important in the immune response. This study seemed to suggest that administration of glycyrrhizin to HIV-positive haemophilia can be effective in preventing the development of AIDS by raising the number of CD4-positive T-lymphocytes.
Influenza A Virus
Viral respiratory infections are the most common diseases that affect people of all ages. The influenza A virus is considered to be a major human pathogen and can cause between 3 and 5 million cases of severe illness and up to 500,000 deaths worldwide in any one flu season4. Currently there are only two classes of drug that are approved in the treatment of the influenza A virus, adamantane derivatives (amantadine and rimantadine) and neuraminidase inhibitors. These drugs are only fully effective if they are administered within a 48 hour period of the onset of symptoms4. Additionally, some influenza A viruses are becoming drug resistant7, which suggests a need for new and novel treatments. In vitro studies have shown that treatment leads to a clear reduction in the number of influenza A-infected human lung cells and that the antiviral activity is mediated by an interaction with the cell membrane which most likely results in reduced endocytotic activity and hence reduced virus uptake1, 4. These results could be significant in helping to develop new anti-influenza therapeutics.
Liquorice has established itself as having many antiviral uses. It shows promise as an ingredient in future antiviral medications and supplements. People infected with the previously listed diseases should consider finding a regular and easy way to introduce liquorice into their diet.
A healthy & easy way to get liquorice in the diet
The team at Gene Eden (www.gene-eden.com) believe in the importance of science. They rely on the best scientific research methods and the most up-to-date reliable research, published in only the well respected scientific journals. Thousands of research papers are meta-analysed using a sophisticated bio-informatics program to identify the most effective and safe natural ingredients. The team recommends taking the Gene-Eden supplement; it is a broad spectrum (effective on many viruses), all natural, antiviral supplement that targets viruses during their latent, active or incubation phase. Gene-Eden contains 5 ingredients, including liquorice extract that has been shown in many research studies to have antiviral activity against a wide range or viruses and which has been used since ancient times for its medicinal properties.
- Fiore, C., Eisenhut, M., Krausee, R., Ragazzi, E., Pellati, D., Bielenberg, J. (2008) Antiviral effects of Glycyrrhiza species. Phytother Res. Vol. 22, No. 2: 141-8
- Asl, M. N., Hosseinzadeh, H. (2008) Review of Pharmacological Effects of Glycyrrhiza sp. and its Bioactive Compounds Phytother Res. 22: 709-724
- Fiore, C., Eisenhut, M., Ragazzi, E., Zanchn, G., Armanini, D. (2005) A history of the therapeutic use of liquorice in Europe Journal of Ethnopharmacology Vol. 99, No. 3: 317-324
- Wolkerstorfer, A., Kurz, H., Bachhofner, N., Szolar, O. H. J. (2009) Glycyrrhizin inhibits influenza A virus uptake into the cell Antiviral Research Vol. 83, No. 2: 171-178
- At last a global response to viral hepatitis. (2010) Bull World Health Organ [online]. Vol. 88, No. 11: 801-802.
- Bongaarts, J., Over, M. (2010) Global HIV/AIDS policy in transition Science Vol. 328, No. 5984: 1359-1360
- Moscona, A. (2009) Global Transmission of Oseltamivir-Resistant Influenza New England Journal of Medicine Vol. 360, No. 10: 953-956