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Balancing Body, Mind, and Spirit with Pure Essential Oils
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Essential Oil Safety


Can Essential Oils Be Used Internally?

Negative Reactions to Aromatic Chemicals

About Birch and Wintergreen Essential Oils



Some of the most beneficial oils can prove harmful under certain conditions. Concentrated oils are very strong, and just because a product is natural doesn’t mean that it’s harmless. Inappropriate use can often lead to adverse and damaging side effects. This is a partial list of medical conditions that warrant avoiding some oils. If you are aware of other contraindications that we’ve omitted, please email us.


Partial List of Medical Conditions that Warrant Avoiding Some Oils

If you are pregnant: avoid Basil, Cedarwood, Clary, Coriander, Hyssop, Jasmine, Juniper, Marjoram. Oregano, Myrrh, Peppermint (which should also be avoided while nursing), Rockrose, Rosemary, Sage, and Thyme.

Please note, the above oils are listed as contraindicated during pregnancy by most aromatherapy authors. However, Martin Watt, the source that I respect the most regarding the safety of aromatic materials used in aromatherapy has this to say: “There are NO essential oils that used externally are proven as harmful to a developing foetus. The vast majority of oils you have listed are common food additives. This is all stuff from the aromatherapy novel writers.”

If you suffer from a seizure disorder: it’s best to avoid Basil, Fennel, Hyssop, Rosemary, and Sage.

To which Martin Watt states: “There is not a shred of evidence that the oils you mention have any adverse effect in epileptics and again most are common food additives.”

If you have hypoglycemia (low blood sugar): avoid Geranium.

To which Martin wrote, “Total and utter B-S.”

If you have high blood pressure avoid: Pine, Rosemary, Sage, and Thyme.

And Martin replies “There is no evidence that the stated essential oils of themselves can increase blood pressure. Of course if someone does not like their smell that might marginally increase it, but probably not.”

Those with kidney problems: should approach Juniper, Sandalwood, and Coriander with caution.

“No evidence and unlikely if the oils are only used externally,” says Martin.



The following oils can cause severe sun damage (photosensitivity): Bergamot, expressed Lime and Rue (very strong); Cumin, Mandarine, Lemon, Tangerine, Orange, Verbena (moderate); Angelica, Caraway, Cassia, Cinnamon Bark, Grapefruit, Honeysuckle Absolute, Laurel Leaf Absolute, Patchouli (mild); Virginia Cedarwood, Dill Weed, and Petitgrain (very mild).

Consider any cold-pressed citrus oil a potential photosensitizer. Steam-distilled citrus oils, on the other hand, do not carry this risk. St. John’s Wort CO2 and infused oil are also photosensitizers.

Clary should not be used when consuming alcohol, because it can greatly increase its effects. Marjoram and Chamomile can cause drowsiness.

If you are using anti-coagulant therapy (blood thinners) avoid oils high in eugenol [Clove, Cinnamon Leaf, and Bay Laurel (pimenta racemosa)].

Two oils with almost identical components that are too dangerous to use lightly, if at all, are Birch (Betula lenta) and Wintergreen. They have their own page with warnings about them.


Sensitizing Oils

Essential oils with a proven or suspected history of causing sensitization (allergies): Aniseed, Bay, Benzoin (indeed, any Styrax oil), Balsam of Peru (VERY HAZARDOUS), Calamus, Cardamom (suspect), Cassia, Cinnamon Bark and Leaf, Citronella, Clary Sage (suspect), Costus, Dill Seed (not weed), Fennel, Bitter, Fig Leaf Absolute, Galbanum Resin (cross sensitizing with Peru Balsam), Hyacinth Absolute (suspect), Jasmine Absolute, Junipers (suspect), Laurel (Bay Laurel), Lemon (suspect), Litsea Cubeba (suspect), Lovage (suspect), Mimosa Absolute, Oakmoss Concrete (suspect), Orange (suspect), Pines (suspect), Rose Absolute (if used in high concentrations), Spearmint, Tolu (balsam, VERY STRONG?), Tagetes, Tolu Balsam, Turpentine, Lemon Verbena (the IFRA strongly advises against the use of Verbena oil in cosmetics or perfume products), Ylangylang (in very high concentrations).

NOTE: Some oils should not be used by anyone except a clinically trained aromatherapist. Among them are Birch, Sage, Thuja, and Wintergreen.

To read more about possible negative reactions to aromatic chemicals, please click here. To read if Benzoin is a Safe Preservative by Martin Watt, click here.


Carcinogenic Oils

Calamus (European and Asian), and Sassafras. (Please note: Sassafras essential oil is banned for use in cosmetics and toiletries in all of Europe.)


Potentially Dangerous Effects

Others have such potentially dangerous effects as to make them too risky to experiment with. The oils on my personal “to be avoided at all costs” list are: Bitter Almond, Calamus (grown in Europe or Asia, the Canadian/USA grown is safer), Yellow Camphor, Horseradish, Mugwort, Mustard, Rue, Sassafras, Southernwood, Tansy (other than Annual Tansy), and Wormwood. I won’t have any of these in my house.


Unsafe Methods of Use

There is one method of using the oils (promoted by a certain MLM that flies in the face of all established safety guidelines for safe and effective use of these powerful essences. For a white paper on the risks of what is commonly called “Rain Drop Therapy” please click here.


Can Essential Oils Be Used Internally?

We do not make claims that the oils should be used internally. In fact, our labels clearly state not for internal use. Why? Because one large essential oil company has taken to carelessly recommending gross overuse of these powerful substances. The oils were never developed for internal use, and it is NOT the most advantageous way to get their benefits.

Now, I use and have used our oils internally, upon rare occasion, and with great respect for their power. The ancient greek term “pharmakopea” has two meanings...“medicine” and “poison”...because anything powerful enough to heal is also powerful enough to do damage.

Our bodies were not designed to metabolize the oils...period...not in their distilled form. Some people will think nothing of adding multiple drops of an essential oil to a glass of cold or warm water, and equating it to, let us say, an herbal tea or tisane...where in actuality they are drinking the equivalent of gallons of the tea in that one bottle of this a good thing? NOT ALWAYS.

I cook with the oils occasionally. I keep a jar of honey with ginger oil in it to add to tea for health reasons. Once or twice a season...and it is two drops of ginger essential oil to 8 ounces of honey. That is ENOUGH for the results I need.

The most ardent recommender of Oregano oil that I personally know recommends its rare and occasional internal use to combat “big bad bugs”...flu, etc...but HE recommends one drop of a 10% dilution on a spoonful of sugar (to get it down...because it can burn the mucous membranes).

This rare and “respectful” use of the essential oils is not what I see recommended, and is not what the people asking about internal use have been mistaught.


Nature’s Gift Disclaimer: The statements made on this website have not been evaluated by the FDA (U.S. Food & Drug Administration). Our products are not intended to diagnose, cure or prevent any disease. If a condition persists, please contact your physician or health care provider. The information provided by this website or this company is not a substitute for a face-to-face consultation with a health care provider, and should not be construed as individual medical advice. The testimonials on this website are from individuals and do not guarantee or imply the same results.

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