Some give you an instant rash, some soothe even the sorest skin. What gives? Judy Johnson finds out

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Essential oils; they’re top of the list of  ingredients to avoid if you’re sensitive  yet small amounts can be truly therapeutic for atopic skin. It’s something that’s baffled me for years, having had multiple reactions to aromatherapy products (all boasting potent essential oils) and yet discovering organic skincare containing them to be one of the best solutions for my oversensitive skin. So what’s going on?

Here’s everything you need to know (read: that I found out after asking the pros A LOT of questions) before you put these plant powerhouses anywhere near your sensitive skin

Dermatologists aren’t generally fans

We know the derms tend to avoid the organic and natural arena, but why? Cosmetic Dermatologist Dr Sam Bunting , my go-to for sensitive skin SOS, explains: "I don't tend to recommend essential oils as I think that whilst some do have beneficial properties, they are complex and potentially unpredictable substances. This means that, despite being 'natural', they may have the ability to trigger irritation or true contact allergy.”

Don’t I know it. Even the better known essential oils can be trouble: "Tea tree oil, which is a very common ingredient in skincare products, contains over 100 natural compounds and I've seen it trigger contact dermatitis in a number of people,” Dr Bunting tells me. "For patients with skin issues, particularly those with sensitivity, I prefer using products formulated in a lab with an ingredients list I can read as they represent a known quantity.”

That said, it’s not a reason to avoid these natural oils altogether - because things are not always as they seem, which leads me to my next point…

Not all plant oils are essential oils

One is far more potent than the other; it takes around 60,000 roses to make 30ml of rose otto,  Formula Botanica  director Lorraine Dallmeier tells me - and it’s all about how they’re extracted. Lorraine breaks it down:

"Not every plant oil will be an essential oil and not every plant will be able to yield an essential oil. It all depends on the plant and the mechanism of extraction.

"Essential oils are generally steam distilled, although it is also possible to create essential oils known as absolutes by using solvents.

"A plant oil is generally a cold pressed oil where e.g. the seeds are crushed to extract the oil - examples include strawberry seed oil, almond oil, or apricot kernel oil.

"A plant extract can be produced in many different ways - through thermal extraction (using heat), ultrasound extraction or supercritical fluid extraction (using CO2). Plants can also be extracted in many different media, including water, alcohol, glycerin, oil or butter. So a plant extract may be completely different to a plant oil which would again be completely different to a plant essential oil.”

Labels aren’t transparent

Given the complexities of essential oils, how do you know what’s in your bottle? It’s not easy - and without talking to a brand, you might never know everything that’s gone into a product.

"It isn’t always easy to tell if a skincare product contains an essential oil,” says Lorraine. "Essential oils will generally be labelled as the name of the plant, together with the word ‘oil’.”

You might see, for example, lavandula angustifolia flower oil for lavender essential oil, or boswellia carterii gum oil for frankincense essential oil. Looking for a specific ingredient? Use the  CosIng  database to find out what it’ll be written as on the label.

However, it’s not always that simple. As readers of this column will know, the sensitive of skin have a nemesis when it comes to labelling known as ‘Parfum’, as Lorraine explains:

"As a manufacturer, it is also possible to list your essential oils under the catch-all heading ‘Parfum’ which provides no information about the types of oils used. However, additional confusion is created by the fact that some preservatives contain fragrance compounds and are therefore declared as ‘Parfum’.

"At Formula Botanica, we are big fans of transparency and we don’t recommend the use of the word ‘parfum' to declare your essential oils - your customers want to know what’s in the formulation after all.”

We really do, especially as certain ingredients are known offenders…

Some oils are known to irritate

"Some oils are known to be more allergenic than others,” says Mandy Head Facial Therapist at Balance Me , naming basil, black pepper, birch, clove, cinnamon, ginger, peppermint and wintergreen as potential problematic ingredients. “But different people will react differently to each individual oil. Skin irritation is an inflammation in the skin and one person’s reaction will differ to another.”

Thankfully, there is an exception to the frustratingly vague labelling rule when it comes to the more irritating oils, too, as Ian Taylor,  Green People’s Cosmetic Scientist  tells me: "If any of 26 specified fragrance compounds are present at levels of greater than 0.01% in rinse-off products or 0.001% in leave-on products then they need to be listed. This applies whether they have been added as isolated chemicals forming part of a more complex perfume blend, or whether they are naturally occurring as part of other ingredients such as most essential oils.

"These 26 fragrance compounds have been singled out because they are amongst the most common substances to cause sensitisation and allergic reactions when applied topically. “

However,  patch testing  is the only way to know for sure - plenty of people will have no reaction at all to the more common culprits. Test on consecutive days, for a minimum of three days, to be certain your skin suits a product; this is recommended for all patch testing but is more important than ever for essential oils, as some, such as cassia, Peru balsam and verbena may only irritate after repeated use.

Going organic is recommended

If you’re going to go down the natural route with your skincare, quality is key - and in this market an organic certification is your best bet.

As Content Beauty and Wellbeing founder Imelda Burke  notes in her book,  The Nature of Beauty:  “A concentrated oil, it is usually extracted via steam distillation and carries the essence of the plant (the volatile components) and the distinctive scent. In some cases the oil is then processed (extended with synthetic chemicals or diluted with vegetable oil) to fit a standardised scent profile. My advice is to always look for authentic, unadulterated, ideally organic essential oils because you might think you are allergic to an essential oil, when in fact you are allergic to the ingredients it has been extracted or diluted with.”

Find out more about shopping for organic skincare here.

Don’t use essential oils in the sun

Even if you don't react to something initially, it could be setting you up for later problems if you don't protect yourself carefully with SPF, as certain essential oils can make you more photosensitive, causing pigmentation or burning once your skin is exposed to UV rays.

"Avoid bergamot (although bergamot that is free of bergapten is less of a concern), cumin, bitter orange and some forms of lemon, lime and grapefruit,” says Imelda.

Dilution is the ultimate key to tolerance

Most people would find themselves in bother if they applied essential oils directly on the skin in their pure form; in skincare, however, it’s the dilution of the essential oils that counts. One of my most beloved brands, Pai, uses essential oils in their sensitive skincare, as does Medik8 - but in minimal amounts, harnessing their therapeutic properties without compromising the health of the skin.

"Many essential oils cannot be used directly on the skin, but most skincare oils will be based on between 1 and 5 per cent dilutions, which typically will not cause any skin concerns,” explains Imelda. "If in doubt, dilute with a base oil such as jojoba, avocado or sweet almond oil.”

It’s not always easy to know how concentrated the oils are within a product, but usually if a brand has used smaller amounts they’ll tell you about it with pride - and again, always patch test to make sure it works for your skin. That way there’ll be no nasty surprises…

Which essential oils have you had issues with, or which brands do you trust? Let me know in the comments!

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