Essential Oils: Drawing Back the Curtain

A while ago, I was invited to an essential oil party. Think Tupperware party, but instead of plastic containers, the host was selling beautifully packaged bottles of essential oils at prices that made my eyes water. The woman presenting was enthusiastic, I’ll give her that. But the information she shared was, at best, incomplete, and at worst, dangerously misleading. She spoke with absolute conviction about oils “curing” conditions, about ingesting them freely, and about layering them directly on skin without dilution. Not once did she mention safety, contraindications, or the very real limits of what the science actually supports.

What frustrated me most was not the sales pitch. It was the realization that this is incredibly common. People share posts, attend parties, and buy into claims without verifying a single one. And because I use essential oils in several of my own products, I have spent considerable time researching them properly. So let’s do this right. Here is what you actually need to know about essential oils.

A Brief History

Essential oils are far from a modern wellness trend. Their use spans thousands of years across multiple civilizations. Ancient Egyptians used aromatic plant extracts in religious rituals, embalming, and medicine as far back as 3500 BCE. They employed a rudimentary form of infusion, soaking plant material in oils or fats to extract aromatic compounds. Evidence of distillation-like processes has also been found in Mesopotamia dating to around 3000 BCE.

In ancient India, the Ayurvedic tradition incorporated aromatic plant extracts into medicine and ritual for millennia. Traditional Chinese medicine similarly used plant-based aromatics extensively. In ancient Greece and Rome, physicians including Hippocrates and Dioscorides documented the medicinal use of plant extracts, with Dioscorides’ work De Materia Medica becoming a foundational medical text for centuries.

The term “essential oil” itself is believed to derive from “quintessential oil,” rooted in the Aristotelian concept of the “fifth essence” or quintessence – the spirit or life force of a plant. The process of steam distillation, which remains the most common method of production today, was refined and documented by Persian physician Avicenna (Ibn Sina) around the 10th and 11th centuries CE, and his contributions laid the groundwork for modern essential oil production.

The modern aromatherapy movement began in the early 20th century, largely attributed to French chemist René-Maurice Gattefossé, who coined the term “aromatherapy” in 1937 after reportedly discovering the burn-soothing properties of lavender oil firsthand. Since then, the industry has grown into a multi-billion dollar global market, with all the benefits and pitfalls that follow.

How Are Essential Oils Made?

Not all essential oils are produced the same way. The method used depends on the plant material involved, and each method has implications for the quality and chemical composition of the resulting oil.

Steam Distillation

The most widely used method. Steam is passed through plant material, causing the volatile aromatic compounds to evaporate. The steam and aromatic vapour are then cooled and condensed, separating into water (hydrosol) and oil. Lavender, peppermint, tea tree, and eucalyptus oils are typically produced this way.

Cold Pressing (Expression)

Used primarily for citrus oils. The rind of the fruit is mechanically pressed or punctured to release the aromatic oils. Because no heat is involved, the resulting oil retains a fresher, more vibrant profile. Lemon, orange, bergamot, and grapefruit oils are produced this way. These oils are also more prone to phototoxicity – an important safety consideration.

Solvent Extraction

Used for delicate flowers that cannot withstand steam distillation, such as jasmine, rose, and neroli. A chemical solvent (often hexane) is used to extract the aromatic compounds, producing what is called a “concrete,” which is then processed with alcohol to yield an “absolute.” These are highly concentrated and largely used in perfumery. Solvent residues, though minimal in the final product, are a consideration for therapeutic use.

CO₂ Extraction

A newer method using carbon dioxide under high pressure to extract aromatic compounds. It produces oils with a fuller chemical profile and no solvent residue. Frankincense and ginger are sometimes extracted this way. It is considered a premium method, and the oils produced are generally of high quality, though the cost reflects this.

The Science Behind Essential Oils: What Do We Actually Know?

This is where things get complicated, and where honest conversation becomes important. Essential oils do contain biologically active compounds. Many of them have demonstrated real pharmacological properties in laboratory settings, including antimicrobial, anti-inflammatory, antioxidant, and antifungal activity. The challenge is the significant gap between what happens in a petri dish and what happens on or in the human body.

The evidence base for essential oils is, in general, considered preliminary. Many studies are small, lack rigorous controls, or are conducted in vitro (in a lab) rather than in vivo (in living subjects). That does not mean essential oils are ineffective. It means we need to be precise about what we claim, and what we do not yet know. The National Institutes of Health (NIH) and other major health bodies acknowledge that some essential oils show genuine therapeutic promise, while cautioning against overstating what current research can support.

Overstated Claims: Where the Evidence Falls Short

Some of the most aggressively marketed claims around essential oils are precisely the ones with the weakest scientific support.

• Treating serious disease: Claims that essential oils can treat, cure, or manage conditions such as cancer, diabetes, or autoimmune diseases are not supported by clinical evidence. In many jurisdictions, making such claims is also illegal under consumer protection and health regulations.
• Detoxification: The “detox” claim is one of the most overused in wellness. The liver and kidneys handle detoxification in the human body. There is no credible evidence that diffusing or applying essential oils accelerates or enhances this process.
• Internal use as a blanket recommendation: The casual recommendation to ingest essential oils – “just add a drop to your water” – ignores significant safety risks. Essential oils are highly concentrated. Even oils that are generally recognized as safe in food flavorings (where they are used in tiny, regulated quantities) can cause harm in larger amounts. Liver toxicity, mucous membrane damage, and drug interactions are documented risks.
• Frankincense curing cancer: This claim circulates widely on social media. While boswellic acids (found in frankincense resin) have shown some anti-tumour activity in laboratory studies, this is a very long way from a clinical cancer treatment. No credible oncology body endorses frankincense as a cancer cure.

Underappreciated Claims: Where the Evidence Is Stronger

It would be equally dishonest to dismiss essential oils entirely. Several have accumulated meaningful research support for specific applications.

• Tea tree oil (Melaleuca alternifolia): Among the most well-researched essential oils. Multiple clinical studies have demonstrated its antimicrobial and anti-inflammatory efficacy, including in the treatment of acne, fungal nail infections, and wound care. A 2017 systematic review published in the International Journal of Antimicrobial Agents confirmed its broad-spectrum antimicrobial activity.
• Lavender (Lavandula angustifolia): Has a substantial body of research supporting its anxiolytic (anxiety-reducing) and sedative effects, particularly via inhalation. A proprietary oral preparation of lavender oil (Silexan) has been studied in clinical trials for generalised anxiety disorder with positive results, published in journals including Phytomedicine.
• Peppermint (Mentha piperita): Good clinical evidence for the topical application of peppermint oil in tension-type headache relief, with a randomized controlled trial published in Cephalalgia showing comparable efficacy to paracetamol for this indication. Enteric-coated peppermint oil capsules also have solid evidence for irritable bowel syndrome symptom management.
• Eucalyptus (Eucalyptus globulus): Its primary active compound, 1,8-cineole (eucalyptol), has demonstrated anti-inflammatory, bronchodilatory, and mucolytic properties. Research supports its use in respiratory conditions, and it is an ingredient in several approved pharmaceutical formulations.
• Frankincense (Boswellia carterii): Boswellic acids have demonstrated meaningful anti-inflammatory activity in studies of conditions including osteoarthritis and asthma. A review in Phytotherapy Research supports its use as an anti-inflammatory agent, though more large-scale clinical trials are needed.

How to Use Essential Oils Topically: A Practical Guide

Topical application is one of the most common and studied uses of essential oils. It is also one of the most commonly misused. Here is what you need to know.

Always dilute

Essential oils must be diluted in a carrier oil before application to the skin. Applying them neat (undiluted) risks chemical burns, sensitization, and allergic reactions. The standard guideline from the National Association for Holistic Aromatherapy (NAHA) is:

• 1% dilution for sensitive skin, children, the elderly, and facial applications (1 drop per teaspoon of carrier oil)
• 2% dilution for general adult use (2 drops per teaspoon of carrier oil)
• 3–5% for localized, short-term application such as muscle pain (3–5 drops per teaspoon of carrier oil)

Suitable carrier oils include jojoba, sweet almond, fractionated coconut, or grapeseed oil. Avoid applying essential oils to broken or irritated skin.

Patch test first

Apply a small amount of the diluted oil to the inner forearm and wait 24 hours before wider use. Sensitivity and allergy are possible with any essential oil, regardless of how “natural” the product is.

Avoid sensitive areas

Keep essential oils away from the eyes, mucous membranes, and broken skin. Do not apply to the inside of the ears or nose.

Be aware of phototoxicity

Cold-pressed citrus oils (bergamot, lemon, lime, grapefruit) contain compounds called furanocoumarins that react with UV light and can cause severe burns and lasting skin discolouration. Do not apply these oils to skin that will be exposed to sunlight.

Special populations

Pregnant women, young children, breastfeeding mothers, and individuals with conditions affecting liver or kidney function should consult a qualified healthcare provider before using essential oils topically. Some oils are specifically contraindicated in pregnancy, including clary sage, rosemary, and camphor.

The Bottom Line

Essential oils are not snake oil, and they are not miracle cures. They are complex, biologically active substances with a long history of use and a growing body of scientific research – some of it compelling, some of it still preliminary, and some of it actively contradicting the claims made by enthusiastic sellers at living room parties.

The responsible path is the same one we advocate for everything on this platform: do your own research, from credible sources. Understand what the science actually says, not what a social media post says it says. Respect the potency of these substances. Use them correctly. And be deeply skeptical of anyone who sells you certainty without evidence.

We use carefully selected essential oils in our products – like our Belly Paste.

References

1. Tisserand, R., & Young, R. (2014). Essential Oil Safety: A Guide for Health Care Professionals (2nd ed.). Churchill Livingstone. https://www.elsevier.com/books/essential-oil-safety/tisserand/978-0-443-06241-4
2. Buckle, J. (2015). Clinical Aromatherapy: Essential Oils in Healthcare (3rd ed.). Churchill Livingstone.
3. Gattefossé, R-M. (1937). Aromatherapy. C.W. Daniel Company.
4. Carson, C.F., Hammer, K.A., & Riley, T.V. (2006). Melaleuca alternifolia (tea tree) oil: A review of antimicrobial and other medicinal properties. Clinical Microbiology Reviews, 19(1), 50–62. https://doi.org/10.1128/CMR.19.1.50-62.2006
5. Kasper, S., et al. (2014). Silexan, an orally administered Lavandula oil preparation, is effective in the treatment of ‘mixed’ anxiety and depression. International Clinical Psychopharmacology, 29(5), 277–288. https://doi.org/10.1097/YIC.0000000000000036
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9. National Association for Holistic Aromatherapy (NAHA). Dilution guidelines. https://naha.org/explore-aromatherapy/about-aromatherapy/safety/
10. National Center for Complementary and Integrative Health (NCCIH). Aromatherapy. https://www.nccih.nih.gov/health/aromatherapy
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