I personally test any essential oil, diluted, on my arm before using on a larger part of my body. Some essential oils are considered ok to use undiluted on the skin if an individual isn’t sensitive to them, but again, always check with a qualified practitioner first.
From a personal perspective, I have first hand experience with the potential problems with undiluted skin exposure. I tried a new massage therapist in our small town since she had a special deal for “aromatherapy” massage. I assumed this meant that there would be essential oils in a diffuser during the massage. To my surprise, as the massage began I felt drops on my back. I realized a few seconds later that she was pouring essential oils on my back… a lot of them. I asked her what oils she was using and she assured me that they were safe, but I got a headache soon after.
In all, she probably poured 80+ drops of undiluted essential oils on my back. I had shivers and a headache for the rest of the day and a large red spot on my back (12 inches in diameter) that lasted several days. Certainly, I should have asked her to stop instead of just asking what the oils were, but what shocked me was that she did not ask if she could use essential oils on me, she did not ask if I was pregnant or had a health condition first and I found out after that she was not even a trained massage therapist or aromatherapist but that she had just “invented” the technique as a way to therapeutically use essential oils.
Again, I should have acted differently and probably asked to see her massage license first, but my experience with this amount of essential oils on the skin was not a positive one.
Bottom Line: Exercise caution and do your research before using essential oils on the skin, even undiluted.
Photosensitivity of Certain Oils
I always include a caution on my recipes that include citrus oils that they may make the skin more sensitive to the sun. These oils have certain constituents that can make the skin more sensitive to UV light and can lead to blistering, discoloration of the skin or burning more easily from minor sun exposure.
Though the risk of photosensitivity or phototoxicity varies based on the way the oil was distilled, oils generally considered photosensitive are: orange, lime, lemon, grapefruit, and bergamot.
Internal Use of Essential Oils
This will be a controversial point, but many essential oils are not safe for internal use and others should be used with extreme caution. Since essential oils are the equivalent of 10-50 cups of herbal tea (depending on the herb) or 20x the recommended dose of an herbal tincture of the same herb, they should only be taken internally in situations where they are absolutely needed and with extreme care (and under the guidance of a trained professional).
Here’s the thing- essential oils are extremely potent plant compounds that can have a very dramatic effect on the body. Many online sources tout their “antibacterial, antimicrobial, antiviral and antifungal” properties. You know what is teeming with many types of bacteria? Your gut.
Research is emerging constantly about our extremely diverse gut microbiomes, but we do not fully understand them yet. We do know that gut health drastically affects other aspects of health and that imbalances in the gut can cause problems in the skin, brain and other parts of the body. The effects of essential oils on gut bacteria have not been well studied yet and the very real antibacterial properties of essential oils may kill many types of bacteria in the gut (including beneficial and necessary bacteria).
In fact, the studies conducted about the antibacterial properties of essential oils compare them to antibiotics and suggest that they may be an effective alternative to antibiotics (here’s one study).
Antibiotics can be life-saving and necessary in some cases (they saved my husband’s life several years ago) but they should not be used regularly, preventatively or without the oversight of a medical professional. If essential oils can act in the same way as antibiotics, we should exercise the same caution in using them internally.
In most cases, some of the same benefits of an essential oil (taken internally) can be obtained by using the herb itself (fresh or dried) or a tea or tincture of that herb.
Many essential oils are considered “GRAS” or Generally Recognized as Safe for food and cosmetic use. However, most essential oils have not been studied, especially in concentrated internal amounts. Things like vinegar, salt and baking soda also are given this status, but that doesn’t mean they should be consumed regularly or in large amounts. Always do your research first!
Essential Oils During Pregnancy or Nursing
Essential oils can affect hormones, gut bacteria and other aspects of health and extreme care should be used when taking them while pregnant or nursing.
There is evidence that essential oils can cross the placenta and get to the baby. The effects of essential oils can be compounded in utero and extreme care should be taken with essential oil use during pregnancy. Again, I’m not saying they should not be used during pregnancy, but that extreme care should be taken and research done first.
I personally would not take any essential oil internally during pregnancy (or even while nursing). At these times, I stick to aromatherapy and very diluted use of approved essential oils in skin care recipes and baths. I also always re-test an oil in a diluted skin test before using it during pregnancy.
Many oils are considered safe during pregnancy, especially after the first trimester (depending on the source), but again, I’d check with a professional and use caution with any herbs used during pregnancy. Even oils that are considered safe may be harmful to certain women and there is some speculation that the actions of some oils on hormones can cause dangerous hormone imbalances during pregnancy.
Oils Considered NOT Safe During Pregnancy
Aniseed, Angelica, Basil, Black pepper, Camphor, Cinnamon, Chamomile, Clary Sage (often used during labor by midwives safely), clove, fennel, fir, ginger, horseradish (should not be used by anyone), Jasmine, Juniper, Marjoram, Mustard, Mugwart (should not be used by anyone), Myrrh, Nutmeg, Oregano, Peppermint, Rosemary, Sage, Thyme, Wintergreen.
I would personally recommend checking with a doctor or midwife before taking an essential oils during pregnancy.
Peppermint essential oil may decrease milk supply while nursing, and as such, I avoid it topically while nursing.
Use on Babies and Children
This is one of the things that concerns me the most with a lot of the essential oil recommendations I see online. In my opinion, essential oils should never be given internally to children or used undiluted on the skin. They should be diluted more than they are for adult application and care should be taken with any essential oils considered “hot” as they may cause damage to the skin.
In general, oils like lavender, chamomile, orange, lemon and frankincense are considered safe for diluted use on children, but I would personally still do a skin test and check with a doctor first.
Some oils have caused seizures in children and extreme caution should be used (this article from a naturopathic pediatrician explains more and gives some case studies– since people have commented, I want to mention that I do think her post is overly alarmist but she makes some good points as well). To clarify- these seizure reactions were rare and most were in people who were predisposed to seizures, but this still isn’t a risk I would take with small children.
Others, like peppermint, rosemary, eucalyptus and wintergreen should not be used around young children or babies. These herbs contain menthol and 1,8-cineole. These compounds can slow breathing (or even stop it completely) in very young children or those with respiratory problems. Of course, they should never be used internally or undiluted on the skin for children, but these particular oils warrant caution even for aromatic use. I would not personally ever use these oils on or around babies for this reason.
This article from the University of Minnesotacautions about the use of peppermint and similar oils in children under six, because: “Menthol-one of the major chemicals in peppermint oil-has caused breathing to stop in young children, and has caused severe jaundice in babies with G6PD deficiency (a common genetic enzyme deficiency) (Price & Price, 1999).”
Since the effects of essential oils are more concentrated on children, it is prudent to exercise extra caution when using essential oils on them. Personally, I stick to using safe essential oils in a diffuser or in very diluted amounts in beauty and cleaning products.
Important note to add: pets can be just as vulnerable.
Essential Oils in Plastics
Another thing that is not often mentioned is that essential oils should never be stored in plastic containers, especially in concentrated forms. Many essential oils can eat through plastics when undiluted, and even when diluted, they can degrade plastics over time.
I make homemade cleaners with essential oils in glass bottles for this reason (even though they are very diluted) and store homemade beauty products in glass whenever possible.
This caution also extends to other surfaces in the house, which I found out the hard way. A bottle of wild orange oil was left on a piece of homemade furniture in our house and when I picked it up the next day, it had stuck to the piece, pulling off the finish and stain when I picked it up. Apparently, there was a little bit of the oil still on the bottom of the bottle (likely from my hand when pouring it). Be extremely careful about leaving any oils, especially citrus oils, on wood or other stained surfaces.
The Good News
Though there are a lot of warnings about safe use of essential oils, they are wonderful natural remedies when used correctly. I hope that this post doesn’t discourage anyone from using essential oils, but rather encourages proper research and safety first.
I use essential oils almost daily, but I make sure to research each oil and its proper use first. It can also be really helpful to find a trained aromatherapist, herbalist or naturopathic doctor to ask specific questions about essential oils. It is also important to make sure any essential oils you use are organic and very high quality.
Safe Ways to Use Essential Oils:
At the end of the day, essential oils can be a great and safe natural remedy, if used safely. The main ways I use essential oils are:
- Aromatically– in a diffuser
- Topically– Diluted in homemade lotion, toothpaste, lotion bars, body butter and other homemade recipes.
I reserve undiluted skin use and internal use for times of real need when the benefits outweigh the risk and I avoid using essential oils in this way on babies/children or when I am pregnant.
What essential oils do you use? Have you ever had any negative effects from their use?
About Katie Wells
Katie Wells, CTNC, MCHC, Founder of Wellness Mama and Wellnesse, has a background in research, journalism, and nutrition. As a wife and mom of six, she turned to research and took health into her own hands to find answers to her health problems. WellnessMama.com is the culmination of her thousands of hours of research and all posts are medically reviewed and verified by the Wellness Mama research team. Katie is also the author of the bestselling books The Wellness Mama Cookbook and The Wellness Mama 5-Step Lifestyle Detox.