We are living in a special time. While scientists scratch their heads to finally find a vaccine for COVID-19, the rest of the world stays cooped up at home watching the drama of the coronavirus pandemic and searching for reliable information on additional ways to defend against the virus.
Colloidal silver, garlic, hot saunas, various teas and tinctures – there are as many natural remedies associated with antiviral effects today as there are rumours about their effects on the body. Companies in the US and Western Europe have already been warned by public authorities not to scare people or mislead people with unproven claims when promoting alternative medicine products to protect against coronavirus.
This commentary is for those who want to avoid getting lost in the rumour mill and are looking for a research-based answer to the question: can essential oils be useful in preventing viruses (and if so, under what conditions)?
General antiviral effects are undisputed It is not news that essential oils from different plants have strong antiviral, antibacterial, anti-toxin and antifungal properties. The valuable properties of plants have been used for health purposes since the earliest civilisations. There are also many historical legends about it, such as how herbal solutions were used to ward off even the plague. And since the 20th century. Numerous aromatherapy studies have scientifically proven the effectiveness of essential oils.
Current research confirms that the constituents of all plant essential oils – terpenes (hydrocarbons) and their derivatives (aldehydes, ketones or alcohols) and phenylpropanoids – have antiviral properties. More or less strong antiviral effects of essential oils have been documented in cases of mumps, chicken pox and, in particular, in the fight against herpes.
There are even studies that show that people who use essential oils for flu and other colds recover three times faster. However, rather than falling into euphoria, it is important to note that the antiviral effectiveness of essential oils from different plants varies considerably. In addition, the way in which essential oils are used is almost decisive.
Virus prevention: when essential oils work and when they don’t To assess the effectiveness of essential oils in stopping the virus, it is worth looking back to the study by Astani A., Reichling J., Schnitzler P., 2010. published in the scientific journal Phytotherapy Research. The authors of the study tested the effects of different essential oils on the herpes virus (HSV-1). The results of the study showed that when essential oils reach the cells just before or just after the virus has entered the body, they do not stop the viral infection. However, essential oils have been shown to have a strong antiviral effect by deactivating free virus particles that have not yet reached healthy cells. This is particularly relevant and encouraging news for people who not only vaporise essential oils with a diffuser, but also use them to clean indoor surfaces.
Whether washing floors, cleaning tables, windowsills, door handles or any other surface with which humans come into contact, essential oils help to deactivate loose virus particles and, by evaporating from surfaces, purify indoor air. This double effect cannot be achieved with any chemical disinfectants or cleaners.
This study also revealed another important fact: when assessing the effects of different essential oils, it was found that among the compounds studied, monoterpene hydrocarbons, and in particular alpha-pinene and alpha-terpineol, were the most superior in their antiviral activity. Moreover, the study revealed a synergistic effect of the active substances: α-pinene and α-terpineol in the essential oil showed a tenfold higher selectivity index and lower toxicity than when isolated alone. This means that natural essential oils with the highest levels of alpha-pinene and alpha-terpineol are the most effective in stopping the spread of the virus.
Smoothing essential oils
It’s time to take a look at which essential oils have the highest alpha-pinene and alpha-terpineol levels. As the table and graph below show, it is not thyme, eucalyptus or even the luxurious tea tree essential oil that has the highest amount of virus neutralising properties. Pine essential oil has the highest total percentage of active compounds.
Comparative table of essential oils
In this context, aromatherapy enthusiasts in Lithuania who look for exotic tea tree oil run the risk of being like the Indians who once traded their gold bars for glass beads. Lithuania’s pine forests are our great gold bars. It is well known that the air in a pine forest is clean and almost free of pathogenic bacteria. Coniferous plants produce phytoncides – biologically active substances that kill or inhibit the growth and development of not only bacteria and viruses, but also microscopic fungi and protozoa.
A typical representative of coniferous phytoncides, Pinus sylvestris essential oil is one of the most suitable and favourable products of the natural environment for defending against a wide range of pathogens, including viruses, that are specific to our environment, thanks to its composition of organic compounds.
Let’s keep our heads down The coronavirus appeared and spread around the world in just a few months. It is therefore premature to draw far-reaching conclusions. It would be irresponsible to say that pine essential oil is a panacea for any virus, let alone the coronavirus, which science is still trying to understand today. It would also be a mistake to use this essential oil anywhere, anytime, anyhow. It is also very important not to use essential oils in excessive amounts, as this can provoke the opposite reaction in the body. As with many other uses of essential oils, the “less is more” rule applies. Finally, no essential oil – neither pine nor tea tree – will protect against the virus if we do not follow basic quarantine requirements and personal hygiene. Ventilate as often as possible, as the air is now less polluted, even in cities. Let’s wash our hands carefully. Keep a safe distance from other people. And, if possible, let’s go for a walk in a remote forest. Especially if it’s a pine forest.
Gražina Vyskupaitienė is a chemist-technologist at Mėta
Sources:
Phytother Res. 2010 May;24(5):673-9. doi: 10.1002/ptr.2955. Comparative study on the antiviral activity of selected monoterpenes derived from essential oils. Astani A., Reichling J., Schnitzler P. Phytother. Res. 1987, Wirkund vov Terpenen auf mikroskopischer Pilze Bakterien und Viren, in Phytotherapy. A.Lembke, R.Deininger.