Antifungal drug treatments for Candida infections have a number of unwanted side effects. These include decimating our probiotic (“good”) bacteria, as well as causing rashes, itching, burning, redness, headaches, diarrhea, gastrointestinal pain and potentially other issues.
Plus, Candida species are becoming increasingly resistant to antifungal pharmaceuticals.
But what about aromatherapy? Can inhaling certain essential oils using aromatherapy do anything to reduce infections of Candida?
The research says yes. In fact, it turns out that some essential oils work better when directly applied. But aromatherapy infusion of some essential oils is apparently more powerful at reducing Candida infections than the direct application of the essential oil according to scientific research.
Study tests essential oils against candida infections
Researchers from Italy’s University of Turin tested the anti-fungal capacity of 46 Candida specimens collected from people who were hospitalized in Turin. They collected 26 specimens of Candida albicans, 10 specimens of Candida glabrata, and 10 specimens of Candida tropicalis. These were collected from the bloodstreams, body fluids, deep tissues, urinary tracts, digestive systems or lungs of different hospital patients.
The microbiologists proceeded to test each of these Candida specimens against several essential oils:
• Thyme (Thymus vulgaris)
• Fennel (Foeniculum vulgare)
• Cloves (Eugenia caryophyllata)
• Pine (Pinus sylvestris)
• Sage (Salvia officinalis)
• Lemon Balm (Melissa officinalis)
• Lavender (Lavandula vera)
The researchers set up individual alcohol dilutions with each essential oil. The dilution factor was 2% for each essential oil solution.
The researchers tested each essential oil solution against each of the 46 specimens of Candida.
Then the researchers set up each essential oil as an aromatherapy against each of the specimens. The essential oil solution did not have direct contact with the Candida species. Only the vapor of each essential oil was exposed to the growing infection.
Then the researchers also tested each Candida strain against two antifungal drugs. These were Fluconazole and Voriconazole. These are two of the most popular antifungal drugs that are prescribed for Candida infections.
Multiple essential oils beat the drugs on contact
The researchers utilized minimal inhibitory concentration (MIC) levels to calculate how well the essential oil could kill the yeasts. MIC levels tell us how little a compound is necessary to inhibit (e.g. kill) a particular type of microbe at a set distance.
This means the lower the MIC, the stronger the compound is: In this case, the more antifungal it is.
The research tested two ranges of MICs – MIC-50 and MIC-90. MIC-50 is the minimum concentration needed to inhibit 50 percent of the yeast populations. And MIC-90 is that amount needed to inhibit 90 percent of the yeasts. This means that the MIC-90 number is typically bigger than the MIC-50 number. This is because it takes more of the substance to inhibit more of the yeast populations.
The researchers found that some of the essential oils in solution inhibited the Candia species better than the two drugs – especially the Thyme and the Pine.
Thyme solution inhibited C. albicans strains with average MICs of 0.03 (MIC-50) and 0.125 (MIC-90). Fennel’s MICs were 0.25 and 1 respectively. Clove was the same. Pine’s average MICs were both 0.06, as were Sage’s. Lemon balm’s MICs for C. albicans were both 1, as were Lavender’s.
Compared to these, fluconazole’s average MICs for C. albicans were 0.5 and 4.0 respectively, and voriconazole’s was 0.06 and 0.12.
Remember that the lower the MIC, the stronger the antifungal.
This means that many of the essential oils inhibited Candida albicans better than the antifungal drugs on average. Especially when it came to inhibiting 90 percent of the yeasts. For 90 percent inhibition, all the essential oils beat fluconazole. And Thyme, Pine and Sage all beat voriconazole for 90 percent inhibition.
Aromatherapy inhibits Candida yeasts even more
But then when the researchers tested the essential oil vapors (aromatherapy), they found some of the MICs were even better. Thyme’s MICs were both 0.0038. Fennel’s were 0.25 and 0.5. Lemon balm’s were both 0.015, and Lavender’s were both 0.06.
Pine’s aromatherapy MICs increased to an average of 1. This means Pine is more antifungal with direct contact than with aromatherapy.
But the other data mean that aromatherapy is better when used with Thyme, Lemon balm and Lavender beat out both antifungal drugs for inhibiting Candida albicans.
The aromatherapy essential oils performed even better against the other Candida species (C. glabrata and C. tropicalis) compared to the antifungal drugs. In these, all the essential oils beat the drugs for average MIC-90s.
The researchers discussed the surprising fact that aromatherapy application beat direct application of the oils:
“Moreover, there is a growing evidence that essential oils in vapour phase are effective antimicrobial systems and that they could have advantages over the use of essential oils in liquid phase, especially in a hospital environment. In fact, our previous studies demonstrated a better activity in vapour phase of some oils (thyme red, fennel, clove, pine, sage, lemon balm and lavender) against human and plant pathogen filamentous fungi.”
Essential oil constituents tested
The researchers also tested all the yeast strains against the most common antifungal constituents among the various essential oils they tested. These included:
• Carvacrol
• Eugenol
• Linalool
• Linalyl acetate
• Thymol
• Pinene
Most of these constituents also performed better than the two antifungal drugs against the 46 Candida yeast specimens. Most of them also performed even better as vapors (aromatherapy).
For example, carvacrol solution had MICs of 0.125 for both 50% and 90%, and 0.0038 for both MICs against Candida albicans strains. Remember that the MIC-90s for fluconazole and voriconazole’s were 4.0 and 0.12 respectively.
But carvacrol’s vapors had average MICs of 0.0038. And Linalool had vapor MICs of 0.0075 – stomping the two drugs.
Aromatherapy is safer
Applying essential oils dermally or internally should come with some caution. This means applying a very small amount first to test. This testing process and direction for direct essential oil application is thus best done with guidance from a healthcare professional.
But aromatherapy doesn’t have this danger. Assuming the infusion process is done correctly, breathing the vapors from aromatherapy has been shown to be extremely safe.
An aromatherapy diffuser needs just a few drops of the essential oil to start working. As the vapors are breathed in, the volatile biochemicals start doing their work. They will have effects upon the respiratory system including the sinuses, the digestive system, the eyes, the ears, and and any part of the skin exposed to the vapors.
Accidentally dropped in a few extra drops into the diffuser? No big deal. A slightly stronger aroma will not cause any harm.
Now consider the difference between breathing aromatherapy vapors and taking antifungal medications. Antifungal drugs can kill much of our digestive probiotics and give us a number of other side effects as mentioned earlier.
Even the researchers were surprised that the aromatherapy vapors were better with the exception of the Pine oil. The researchers discussed the reasons for the differences:
“The different antifungal activity in liquid and vapour phase could be due to the characteristics of essential oils such as high hydrophobicity and volatility. In fact, when added to a medium, the essential oil distributes more or less into the aqueous phase depending on its relative hydrophobicity. In the liquid phase, the activity depends upon the diffusibility and solubility of the essential oils in the medium while in the vapour assay it depends upon the volatility.”
Essential oils are seriously antifungal
One of the special effects of the essential oils against the Candida species is that their 50% inhibition and 90% inhibition numbers were often close or the same. This compares with the drugs, which needed much greater concentrations to get to the 90% inhibition.
What does this say about essential oils? It says that they are seriously antifungal. The yeasts can’t tolerate the essential oils, and can’t get used to them either.
That is basically what the difference tells us. When the 90% is much greater than the 50% inhibition MICs, it tells us that as the concentration of the antifungal grows, many yeasts begin to tolerate the antifungal. Many figure out how to survive despite it.
This is the beginning of resistance. As more yeasts learn the path of resistance, the more they become resistant to the drug. (They often do this with an exchange of information through DNA packets.)
Essential oils are antifungal against a wider range of species of yeasts. A 2013 study from Spain showed that essential oils were antifungal against other yeast and fungi species such as Debaryomyces hansenii, Rhodotorula mucilaginosa, Pichia carsonii, Alternaria alternata, Mucor racemosus and Penicillium chrysogenum.
This antifungal properties of some essential oils includes species that are resistant to antifungal drugs. The researchers confirmed that several essential oils were also active against those yeasts that were resistant to the fluconazole and voriconazole antifungal drugs:
“MIC values showed that essential oils activity is higher than that obtained with the conventional antifungal drugs tested against C. glabrata and C. tropicalis, both resistant to fluconazole and voriconazole.”
They also concluded:
“Overall, our experimental data give substantial support to previous empirical evidence or literature data on the anticandidal activity of different essential oils.”
What does this tell us about nature’s antifungals: Nature is smarter.
REFERENCES:
Mandras N, Nostro A, Roana J, Scalas D, Banche G, Ghisetti V, Del Re S, Fucale G, Cuffini AM, Tullio V. Liquid and vapour-phase antifungal activities of essential oils against Candida albicans and non-albicans Candida. BMC Complement Altern Med. 2016 Aug 30;16(1):330. doi: 10.1186/s12906-016-1316-5.
Ruiz-Navajas Y, Viuda-Martos M, Sendra E, Perez-Alvarez JA, Fernàndez-Lòpez J. In vitro antioxidant and antifungal properties of essential oils obtained from aromatic herbs endemic to the southeast of Spain. J Food Prot. 2013;76:1218–1225. doi: 10.4315/0362-028X.JFP-12-554.