In recent years, essential oils have gained popularity not only for their aromatic qualities but also for their potential health benefits. Among these benefits, the ability to boost the immune system against viral infections stands out, especially given the recent global pandemic. Essential oils, rich in aromatic compounds called terpenes, offer various mechanisms through which they can protect and enhance our health against viruses.
Understanding Terpenes, the Aromatic Molecules Found in Plants
Terpenes are natural compounds found in the essential oils of plants. They provide the distinct aromas and flavors we associate with different herbs, fruits, and flowers. More importantly, terpenes have significant health-promoting properties, including antimicrobial, anti-inflammatory, and immune-modulating effects. These properties make terpenes key players in strengthening the immune system and combating viral pathogens (Orosco, 2024; Iqhrammullah, 2023; Reichling, J, 2021)
These bioactive molecules can exert antiviral effects by regulating the host’s (human) immune system and controlling the levels of reactive oxygen species. When viruses infect our bodies, they can cause the production of harmful oxygen byproducts called reactive oxygen species (ROS). These unstable molecules can damage cells and weaken our immune system, making it harder for our bodies to fight off infections.
Research indicates that terpenes combat viruses through a variety of mechanisms. Scientists have demonstrated that these compounds can directly inhibit viral infections in both in vitro (cell lines) and in vivo studies (animal models). They achieve this by interfering with viral replication and/or regulating the host cell's intracellular signaling pathways. This multifaceted approach makes terpenes, and thus essential oils, a promising avenue for supporting antiviral therapies (Ponticelli, 2023).
Key Terpenes and Their Immune-Boosting and Antiviral Mechanisms
Beta-Pinene – Common in rosemary and parsley, beta-pinene inhibits enzymes needed for viral replication and possesses antioxidant properties that protect cells from damage during viral infections. Furthermore, a reported study demonstrated the Japanese cypress essential oil vaporized with a humidifier in hotel room, containing both alpha and beta-pinene, boosted the immune system by increasing Natural Killer cells and decreasing stress hormones (Li et al., 2009).
Explanation: These enzymes are crucial for the virus to reproduce and spread within the host's body. By inhibiting these enzymes, beta-pinene helps to prevent the virus from multiplying, thereby aiding in the fight against viral infections.
Beta-Caryophyllene – Extracted from cloves and black pepper, B-caryophyllene binds to cannabinoid receptors in humans, which has been shown to reduce inflammation and potentially inhibit viral entry by targeting the spike protein (Mazzantini et al., 2024; Iqhrammullah, 2023; Chatow et al., 2021; Astani, 2014).
Explanation: Beta-caryophyllene is a unique terpene because it interacts with cannabinoid receptors in the body, specifically the CB2 receptors, primarily found in the immune system. By binding to these receptors, beta-caryophyllene can help regulate the immune response, reduce inflammation, and potentially inhibit viral replication. This makes it a powerful component for boosting overall immune health and fighting off viral infections.
Now, when it comes to viruses like SARS-CoV-2 (the virus that causes COVID-19), beta-caryophyllene might have another important role. This virus uses a part called the spike protein to attach to our cells and get inside to cause an infection. Scientists think that beta-caryophyllene could attach to this spike protein, making it harder for the virus to connect to our cells. If the virus can't connect and get inside, it can't make us sick as easily (Iqhrammullah, 2023).
These combined effects make beta-caryophyllene a helpful natural compound for our immune system and for viral infections like COVID-19.
Linalool – Found in lavender, birch bark, and basil, linalool disrupts viral lipid membranes and modulates the immune response by reducing pro-inflammatory cytokines (e.g., IL1-B, IL-6, and others) thus helping in managing inflammation caused by viral infections (Nakamura et al., 2009; Santos et al., 2022).
Explanation: Cytokines are like messengers in your body that help coordinate the immune response. When you're sick or have an infection, these messengers tell your immune system where to go and what to do to fight off the illness. They help ramp up the defense system to attack the invaders and also help calm things down once the threat is under control.
Limonene – Abundant in citrus fruits, limonene disrupts the viral envelope, making it harder for viruses to infect cells, and helps modulate the immune system (Nagoor Meeran et al., 2021; Astani and Schnitzler, 2014).
Explanation: Many viruses, including some that cause common illnesses, have an outer layer called the viral envelope. It protects the virus and helps it infect host cells. Without its protective envelope, the virus can't survive. The viral envelope is crucial for the virus to attach to and enter host cells. Once the envelope is disrupted, the virus is unable to infect cells, effectively rendering it inactive or "dead."
Myrcene – Present in mangoes and lemongrass, myrcene not only inhibits viral replication but also reduces inflammation, helping to alleviate symptoms and prevent severe viral effects by reducing tissue damage caused by viral infection (Surendran et al., 2021).
Humulene – Found in hops and sage, humulene helps modulate the immune response and reduces inflammation, which is crucial in the management of viral infections (El-Beltagy et al., 2011).
Alpha-Pinene, Eucalyptol, Terpinolene, and Geraniol – These terpenes inhibit various stages of viral replication and enhance immune function, providing a broad spectrum of protection and relief (Iqhrammullah, 2023; Kim et al., 2020).
Enhancing Immunity with Aromatic Blends
Leveraging the power of these terpenes, specific aromatic blends can be used in various delivery systems such as candles, mists, and diffusers to enhance immune function and provide a pleasant environment. Here are two specific formulas that incorporate these powerful terpenes:
MOJO: Inspired by the Japanese practice of forest bathing, known as "Shinrin-yoku," which involves immersing oneself in the forest atmosphere, this blend captures the essence of nature's immune-boosting properties. Japanese forest bathing has been used as a therapy in Japan, with studies showing that the aromatic terpenes from the trees help upregulate the immune system by increasing natural killer (NK) cells, which then creates a cascade of beneficial effects (Kim 2021; Cho et al., 2017; Li et al., 2009).
Combinations such as fir balsam, black spruce, and cypress from the organic essential oils list offer a forest-like, refreshing aroma that not only purifies the air but also has mild antiviral effects thanks to compounds like alpha-pinene and eucalyptol. This blend is invigorating to the senses, as though taking a nature walk in the forest.
PROTECT: With a robust composition featuring basil, black pepper, and cloves, this blend harnesses the power of beta-caryophyllene along with organic essential oils like neroli, green mandarin and sweet orange. These contribute not only to a refreshing aroma but also to an enhanced immune defense, particularly useful during the flu season or viral outbreaks.
Both blends include ingredients like Copaiba oil, hops, and rosemary, all rich in beta- caryophyllene. This terpene's binding with cannabinoid receptor (CB2) can reduce inflammation and potentially inhibit viral replication. By diffusing or lighting a candle, Protect can create an environment that not only smells good but also supports your immune system.
Practical Application
Using these essential oils through traditional candles, diffusers, or as room sprays can help distribute their beneficial properties throughout your environment. Regular use, particularly in places like homes or offices where people gather, can be an effective way to support the body's natural defense systems as well as a delight to your olfactory system providing a sense of calm, invigoration, or stress relief.
Conclusion
The use of essential oils as a natural method to boost the immune system is grounded in both tradition and modern science. Terpenes in these oils enhance the immune response and may disrupt viral activities (depending on the type of virus), making essential oils a valuable complement to other health-maintaining practices. By understanding the properties of each terpene and utilizing them through pleasant aromatic blends, we can take a proactive step towards maintaining health and well-being in a natural, enjoyable way.
REFERENCES:
Allahverdiyev, A.M., Bagirova, M., Yaman, S., Koc, R.C., Abamor, E.S., Ates, S.C., Baydar, S.Y., Elcicek, S., and Oztel, O.N. (2013). Chapter 17 - Development of New Antiherpetic Drugs Based on Plant Compounds. In Fighting Multidrug Resistance with Herbal Extracts, Essential Oils and Their Components, M. K. Rai and K. V. Kon, eds. (Academic Press), pp. 245–259.
Astani, A., and Schnitzler, P. (2014). Antiviral activity of monoterpenes beta-pinene and limonene against herpes simplex virus in vitro. Iran. J. Microbiol. 6, 149–155.
Chatow, L., Nudel, A., Nesher, I., Hayo Hemo, D., Rozenberg, P., Voropaev, H., Winkler, I., Levy, R., Kerem, Z., Yaniv, Z., et al. (2021). In Vitro Evaluation of the Activity of Terpenes and Cannabidiol against Human Coronavirus E229. Life 11. 10.3390/life11040290.
Cho, K.S., Lim, Y.-R., Lee, K., Lee, J., Lee, J.H., and Lee, I.-S. (2017). Terpenes from Forests and Human Health. Toxicol. Res. 33, 97–106.
El-Beltagy, A.E., et al. (2011). Essential oils from aromatic plants and their potential uses in viral infections: humulene as an example. Egyptian Journal of Virology, 8(2), 33-40.
Iqhrammullah, M., Rizki, D.R., Purnama, A., Duta, T.F., Harapan, H., Idroes, R., and Ginting, B. (2023). Antiviral Molecular Targets of Essential Oils against SARS-CoV-2: A Systematic Review. Sci. Pharm. 91, 15.
Kim, T., Song, B., Cho, K.S., and Lee, I.-S. (2020). Therapeutic Potential of Volatile Terpenes and Terpenoids from Forests for Inflammatory Diseases. Int. J. Mol. Sci. 21. 10.3390/ijms21062187.
Li, Q., Kobayashi, M., Wakayama, Y., Inagaki, H., Katsumata, M., Hirata, Y., Hirata, K., Shimizu, T., Kawada, T., Park, B.J., et al. (2009). Effect of phytoncide from trees on human natural killer cell function. Int. J. Immunopathol. Pharmacol. 22, 951–959.
Mazzantini, C., El Bourji, Z., Parisio, C., Davolio, P.L., Cocchi, A., Pellegrini-Giampietro, D.E., and Landucci, E. (2024). Anti-Inflammatory Properties of Cannabidiol and Beta-Caryophyllene Alone or Combined in an In Vitro Inflammation Model. Pharmaceuticals 17. 10.3390/ph17040467.
Nagoor Meeran, M.F., Seenipandi, A., Javed, H., Sharma, C., Hashiesh, H.M., Goyal, S.N., Jha, N.K., and Ojha, S. (2021). Can limonene be a possible candidate for evaluation as an agent or adjuvant against infection, immunity, and inflammation in COVID-19? Heliyon 7, e05703.
Nakamura, A., Fujiwara, S., Matsumoto, I., and Abe, K. (2009). Stress repression in restrained rats by (R)-(-)-linalool inhalation and gene expression profiling of their whole blood cells. J. Agric. Food Chem. 57, 5480–5485.
Ninkuu, V., Zhang, L., Yan, J., Fu, Z., Yang, T., and Zeng, H. (2021). Biochemistry of Terpenes and Recent Advances in Plant Protection. Int. J. Mol. Sci. 22. 10.3390/ijms22115710.
Orosco, F., and Quimque, M. (2024). Antiviral potential of terpenoids against major viral infections: Recent advances, challenges, and opportunities. Journal of Advanced Biotechnology and Experimental Therapeutics 7, 221.
Peterfalvi, A., Miko, E., Nagy, T., Reger, B., Simon, D., Miseta, A., Czéh, B., and Szereday, L. (2019). Much More Than a Pleasant Scent: A Review on Essential Oils Supporting the Immune System. Molecules 24. 10.3390/molecules24244530.
Ponticelli, M., Bellone, M.L., Parisi, V., Iannuzzi, A., Braca, A., de Tommasi, N., Russo, D., Sileo, A., Quaranta, P., Freer, G., et al. (2023). Specialized metabolites from plants as a source of new multi-target antiviral drugs: a systematic review. Phytochem. Rev., 1–79.
Reichling, J. (2022). Antiviral and Virucidal Properties of Essential Oils and Isolated Compounds - A Scientific Approach. Planta Med. 88, 587–603.
Salehi, B., Upadhyay, S., Erdogan Orhan, I., Kumar Jugran, A., L D Jayaweera, S., A Dias, D., Sharopov, F., Taheri, Y., Martins, N., Baghalpour, N., et al. (2019). Therapeutic Potential of α- and β-Pinene: A Miracle Gift of Nature. Biomolecules 9. 10.3390/biom9110738.
Santos, S., Barata, P., Charmier, A., Lehmann, I., Rodrigues, S., Melosini, M.M., Pais, P.J., Sousa, A.P., Teixeira, C., Santos, I., et al. (2022). Cannabidiol and Terpene Formulation Reducing SARS-CoV-2 Infectivity Tackling a Therapeutic Strategy. Front. Immunol. 13, 841459.
Surendran, S., Qassadi, F., Surendran, G., Lilley, D., and Heinrich, M. (2021). Myrcene-What Are the Potential Health Benefits of This Flavouring and Aroma Agent? Front Nutr 8, 699666.
Trilogía 6 Terpenes Your Immune System Will Love. https://trilogia.com/blogs/stories/6-terpenes-your-immune-system-will-love.
Wani, A.R., Yadav, K., Khursheed, A., and Rather, M.A. (2021). An updated and comprehensive review of the antiviral potential of essential oils and their chemical constituents with special focus on their mechanism of action against various influenza and coronaviruses. Microb. Pathog. 152, 104620.
