The One Skincare Ingredient Most Beauty Experts Want You To Avoid

Dear Daniela,

Are essential oils good or bad in skincare? I see so many people saying they can be irritating and bad for sensitive skin but then loads of people swear by them, too. Also, are essential oils the same thing as face oils, and are those good or bad? Please help!

Jazz, 29

It really frustrates me how certain topics in beauty turn into black-and-white, them-and-us issues. Certain accounts and influencers would have you believe that an ingredient or product is "perfect for everyone" or "must be avoided at all costs" and then the two sides angrily flood one another’s comments sections and duke it out on Twitter.

In reality, most things in beauty occupy something of a grey area. Alcohol in skincare is not always bad, parabens are unlikely to be problematic and some people can tolerate fragrance in their moisturiser just fine. However, these opinions are not catchy or memorable, nor do they conjure up a sense of exclusive community through secret knowledge. 

Essential oils are a little bit like this – sometimes tolerable, sometimes problematic. I asked Dr Mary Sommerlad, a consultant dermatologist in the NHS and at 108 Harley Street, to explain it to me. "As a doctor, it’s important to remember that I only see the complications and for that reason, I’m not a fan of using essential oils neat," cautioned Dr Sommerlad. "I see people who have been using tea tree oil on their face and then start getting lots of irritation and dryness, for instance."

Tea tree is a good example as it’s one of the most popular essential oils in skincare, especially for oily skin. Dr Sommerlad explained that while there has been some interesting research into the use of tea tree extract for breakouts, the problem is that people extrapolate this far too quickly. "People attempt to make DIY or home remedies, often using the tea tree oil undiluted (or neat) and then it’s very common to experience dryness, irritation and sensitivity, especially if someone has eczema, rosacea or psoriasis. That’s a recipe for trouble," added Dr Sommerlad.

That being said, Dr Sommerlad was quick to remind me that there are professionals who are very skilled in using essential oils for therapeutic purposes, like aromatherapy, for example. What Dr Sommerlad is advising against is playing chemist at home and trying to make a face mask or treatment with essential oils that could really upset your skin. "If you do want to try and use essential oils at home, always do a patch test and wait 48 hours to see if you have an allergic response, and I would strongly advise against using them if you do have eczema, rosacea or psoriasis," said Dr Sommerlad.

Okay, I hear you say, what about if I dilute them? Well, a whole host of beauty products across skincare and cosmetics use essential oils in tiny trace amounts, blended with stabilising and cocooning ingredients that make them less problematic. "They’re usually found in moisturisers and often there will be glycerin or shea butter or hyaluronic acid also included," explained Dr Sommerlad. "Many people will be able to tolerate these just fine, especially if you don’t have sensitive skin."

I’m definitely more on the sensitive side but after examining some of my most used products, I was surprised to find that a lot of them feature essential oils, just in very, very small amounts. There is a risk that your skin can become sensitised to something over time, as Dr Sommerlad noted. "It’s not the first exposure that causes a reaction; it’s the second or subsequent exposures, because your body has to build up the antibodies that cause the allergic reaction. The classic example is somebody saying, ‘I’ve used this perfume for 10 years. This is my signature perfume, how are you telling me I'm allergic to it?’ That's because you become allergic. Allergies are actually more commonly developed the older you get."

Now on to your point about face oils. They may contain essential oils but facial oils are more often primarily composed of things like argan oil and camellia oil, which are fatty oils and so offer that super slick, smooth feeling. Meanwhile, essential oils are composed of the essence of a plant’s fragrance, hence the name. "I do not know any dermatologists who use facial oils in their skincare routines," said Dr Sommerlad diplomatically. "I do, however, see lots of patients whose use of facial oils has caused them to have really severe breakouts, quite sore spots and excess oil production. Your skin is making oil all the time, called sebum, and this sebum is your best moisturiser because your body has made it to counteract the effects of the environment you’re in. The main reason people use facial oils is to try and lock moisture into the skin. However, lots of moisturisers already contain moisture-locking ingredients in a more balanced way," she explained.

Of course, as Dr Sommerlad reminded me, people often use facial oils for sensory reasons – they feel gorgeous, aid massage, smell divine and leave the skin gloriously soft. If you can use a facial oil without negative effects, I won’t try and stop you! But you may find over time that it gets a little much more for your skin. This is the unique challenge of beauty: things have to work, sure, but we also expect them to smell nice, look good on our shelf and feel luxurious...

Daniela