Herbs and fruits can be used as a natural remedy for the treatment of COVID-19. For example, vitamin C containing foods have been used for decades for treating influenza.
The common cold, SARS-CoV-1, and SARS-CoV-2 fall under the same coronavirus family. All these viruses can be considered the same type of virus, and the same type of medication can be applied1. Therefore, vitamin C could be effective against COVID-19.
Many herbs and foods display antiviral and immunomodulatory activities. Aloe vera, Korean angelica (angelica gigas), Mongolian milkvetch (Astragalus membranaceus), reishi mushroom (Ganoderma lucidum), ginseng (Panax ginseng), and Chinese skullcap (Scutellaria baicalensis) have immunomodulatory properties. These plants stimulate cytokines, activate lymphocytes, increase natural killer cell counts, and enhance macrophage actions1.
Rice bran, wheat bran, Hina (Lawsonia alba), Echinacea (Echinacea purpurea), Ceylon leadwort (Plumbago zeylanica), and velvetleaf (Cissampelos pareira Linn) also have immunomodulatory properties by stimulating phagocytosis. Using these immunomodulatory foods and herbs could enhance the immune system and protect the body against COVID-19.
Recent studies have shown that the extracts of garlic, ginger, Korean red ginseng, eucalyptus, tea tree, Tianmingjing, Machixian, fish mint, Chinese mahogany, cape jasmine exhibit antiviral activity against the influenza virus1.
Brief information about some plants that are thought to be effective against coronavirus is given below.
Eucalyptus essential oil
Eucalyptus essential oil can be used as a natural remedy for the treatment of COVID-19.
Its essential oil improves the innate cell-mediated immune response used as an immunoregulatory agent against infectious diseases.
Eucalyptus contains a chemical called eucalyptol, which works as a natural decongestant, and cough suppressant by helping break down mucus and phlegm and opening up airways.
Aloe vera is another alternative natural remedy for the treatment of COVID-19.
Polysaccharides in aloe Vera irritate the immune system. However, these polysaccharides are not a toxin. The immune system considers these compounds as a threat. That is the reason why people who eat aloe vera have an excellent immune system2.
The beverages prepared from Aloe vera juice contain detoxifying properties that can help to cleanse the circulatory system and digestive systems. When the absorption level of nutrients increases, it results in better circulation of blood and improves health. When the blood is rich in oxygen, it transports nutrients to cells efficiently. Healthy cells promote the ability of the body to counteract infections by strengthening the immune system3.
Reishi mushroom (Ganoderma lucidum)
Reishi extract contains a high concentration of beta-glucans and a polysaccharide. These chemicals are known as immunomodulators, which improve the function of the immune system.
Reishi mushrooms also contain triterpenes, which give reishi its bitter taste as well as its calming properties. These active chemicals make the reishi mushroom a natural antiviral, antibacterial, and antifungal.
According to some studies, reishi mushrooms enhance the immune system and increase natural killer cells (a white blood cell)4.
Ginseng (Panax ginseng)
Ginseng is quite beneficial to boost the immune system and helps the body fight off infection and disease. Roots, stems, and leaves of ginseng are used to maintain immune homeostasis and enhance resistance to illness or infection.
Several studies have shown that American ginseng improves the performance of cells that play a role in immunity. Ginseng controls each type of immune cell, including macrophages, natural killer cells, dendritic cells, T cells, and B cells5.
Echinacea (Echinacea purpurea)
The medicinal part is derived from the aerial parts and the root of the herb.
Echinacea is commonly used for preventing and alleviating the symptoms of bacterial and viral infections. Its preparations exert antioxidant and anti-inflammatory activity espousing its potential immunomodulatory activities6.
According to some studies, purified compounds from Echinacea (glycoproteins, soluble polysaccharides, phenolic compounds, and alkamides) could induce transcriptional changes that activate immunomodulation pathways.
Ceylon leadwort (Plumbago zeylanica)
Plumbagin and chloroform extracts of Ceylon leadwort root showed antibacterial activity against Escherichia coli, Salmonella typhi, and Staphylococcus aureus.
The inhibition against Klebsiella pneumonia, Serratia marcescens, and Bacillus subtilis was moderate and low against Proteus Vulgaris and Pseudomonas aeruginosa. Disc diffusion experiments show that the alcohol extract exhibited moderate activity, and the aqueous extract exhibited weak activity against the bacterial strains.
The bioactive compound plumbagin and Ceylon leadwort root extract show a wide spectrum of antibacterial activity, antifungal, and anticarcinogenic activity. It also has antitumor activity. They are also known to possess antifertility, germicidal, antileprotic, and anti-inflammatory activities.
The plant possesses central nervous system stimulatory, hepatoprotective, antioxidant, hypolipidaemic, and anti-atherosclerotic properties7.
Some studies on mice reveal that garlic protects the body from intranasally inoculated influenza viruses, causing infections and enhancing neutralizing antibody production when given with influenza vaccine8.
Fresh garlic extract is virucidal against all viruses. The virucidal activity of commercial products is dependent upon their preparation processes. Those products producing the highest level of allicin and other thiosulfinates have the best virucidal activity8.
Garlic has been shown to enhance T-cells’ pathogen-attacking activity, neutrophils, and macrophages, increase interleukin’s secretion and increase natural killer cell activity.
In individuals eating the equivalent of two bulbs a day, killer cell activity increased by 140%. In those consuming 1,800mg of odorless aged garlic daily, killer cell activity increased 156%.
Ginger boost immune health due to its strong anti-inflammatory and antioxidant effects. Acute inflammation has an important role in a normal immune response.
Antioxidant-rich foods and beverages like ginger shots may combat inflammation and keep your immune system healthy9.
Many studies suggest that ginger can enhance immune response due to its antiviral and antibacterial properties.
One test-tube study found that fresh ginger had antiviral effects against the human respiratory syncytial virus (HRSV), causing respiratory infections and boosting the immune response against HRSV9.
1. Panyod, S., Tang Ho, C., & Sheen, L. Y., (2020) Dietary therapy and herbal medicine for COVID-19 prevention: A review and perspective. Journal of Traditional and Complementary Medicine, 10(4), DOI: 1016/j.jtcme.2020.05.004
2. Aloe Vera: The Ultimate Guide. Retrieved from the Natural Healers websites: https://www.naturalhealers.com/blog/aloe-vera-ultimate-guide/
3. Health benefits of Aloe-Vera. Retrieved from the Health Benefit Times websites: https://www.healthbenefitstimes.com/aloe-vera/
4. REISHI MUSHROOMS: THE QUEEN OF THE MUSHROOM KINGDOM. Retrieved from the Your Super websites: https://yoursuper.com/pages/reishi-mushroom-benefits
5. Health benefits of ginseng. Retrieved from the Health Benefit Times websites: https://www.healthbenefitstimes.com/ginseng/
6. Dobrange, E., Peshev, D., Loedolff, B., & Van den Ende, W. (2019). Fructans as Immunomodulatory and Antiviral Agents: The Case of Echinacea. National Library of Medicine. 16;9(10):615. DOI: 10.3390/biom9100615.
7. Plumbago Zeylanica Linn. Retrieved from the Vasu Healthcare websites: https://www.vasuhealthcare.com/ceylon-leadwort/
8. Retrieved from the Association for the Advancement of Restorative Medicine websites: https://restorativemedicine.org/library/monographs/garlic/
9. Kubala,, (2019). What Are Ginger Shots? Everything You Need to Know. Retrieved from the Healthline websites: