DIY facial ingredients you should never put on your face according to skin scientist Dr Michele Squires

Those at-home coffee scrubs and egg white face masks aren’t as safe for your skin as you may think. Dr. Michele Squire explains the ingredients we should steer clear of when making our own skincare.

Isolation and salon closures mean we’ve had to turn to at-home DIY beauty solutions to get us through. The extra time at home has also encouraged our creativity and alchemist abilities and sees us whipping up cellulite-busting coffee scrubs in the kitchen sink and repurposing pantry staples into face masks.

Although you might have discovered a new love for creating your own clean skincare, or the savviness of reusing whatever is in the fridge to soothe your #isoskin, there are some ingredients that should be left out of your next concoction. Dr Michele Squire, PhD scientist and founder of QR8 runs us through the stuff to keep out of your skincare.

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“Let’s start with something that should be completely benign. Any homemade skincare that contains water should be used immediately and the left-overs discarded if they don’t also contain a proven preservative system.

Even some oil-based remedies can have issues if stored in a humid or steamy bathroom. Bacteria and fungi will thrive in unpreserved water-based DIY products. Essential oils are often used to ‘preserve’ DIY products but they are not broad-spectrum (effective against a wide variety of microbes). High concentration of essential oils can also cause contact irritant dermatitis.”

Sugar, salt, coffee grounds and baking soda

“Or any similar home-made granular facial exfoliants. These are OK for the body where skin can take harsher treatment, and when used very gently on dry lips, but there’s a very real possibility that over-exuberant scrubbing can lead to skin barrier damage and further dryness.”

Natural acids

“Like lemon juice, apple cider vinegar or vinegar. Apart from the fact that neither of these have any evidence that they do anything for skin, they can both cause harm. Vinegar, especially ACV, contains 4–8% acetic acid, which can cause chemical burns when applied topically.

Lemon juice (and other citrus fruit juices) can cause something called ‘phytophotodermatitis’ which is burning and blistering of the skin after it is exposed to chemicals in certain plants, then exposed to sunlight.”


“You might get a bit of exfoliation due to the microcrystalline cellulose and corn starch that aspirin tablets contain, but if you thought they contain salicylic acid (BHA), think again. The active ingredient in aspirin is acetylsalicylic acid – a related but different chemical, and one that has zero proven exfoliating ability. It’s more likely to just lead to further skin irritation, so another DIY hack to steer clear of.”

Raw egg white

“Whilst the proteins in raw egg white might actually work as humectants in a face mask, there’s a risk that accidentally ingesting the egg whites while making or applying your mask can lead to food poisoning with a bug called salmonella.

Most DIY egg white mask recipes also add things like lemon juice and acids that we have already seen aren’t great for skin. There are plenty of well-priced moisturising masks available that are safe and effective. Stick with one of those!”