My Top Ten Ingredients to Avoid

Ingredient lists can be overwhelming, especially when you're trying to identify your triggers. People ask me constantly: "What's the one ingredient I should dodge?"

That's impossible to answer. It depends on your skin type, and most of us are sensitive to more than one thing. But I do have a list of the top ten ingredients worth avoiding.

This isn't definitive (ten is limiting!). But it covers the ingredients I'm most allergic to and the ones we get asked about constantly. Plus some that are particularly problematic because they're marketed as natural or safe when they're not.

Detergents: The Barrier Breakers

Detergents strip away your skin's natural protective oils, leaving it exposed and prone to reaction. They're also incredibly alkaline, which disrupts your skin's pH balance and damages the acid mantle.

You probably already know about Sodium Lauryl Sulfate (SLS). It's a surfactant that characteristically induces a dose-related increase in transepidermal water loss. In plain English? It punches holes in your skin barrier and lets all the moisture escape. Studies show it damages the epidermal barrier function, which is why your skin feels tight and angry after using products containing it.

1. Cocamidopropyl betaine — a foaming agent hiding in face wash, hand wash and shampoo. It's supposedly gentler than SLS. It's not. This one's particularly irritating for eczema-prone skin.

2. Ammonium lauryl sulfate (ALS) — the common name for ammonium dodecyl sulfate. Research shows solutions containing 1.25%-27.4% detergent cause increasing irritation with concentration, and solutions of 2%, 10%, and 20% ALS were highly irritating. Your skin knows the difference between clean and stripped.

Humectants: Not All Moisture Is Good Moisture

A humectant is an ingredient that preserves or boosts skin's moisture levels. Sounds good in theory. In practice, some of them are devastating for sensitive skin.

3. Propylene Glycol — commonly causes irritant contact dermatitis and can cause contact urticaria and sensory irritation. If you have eczema, this is public enemy number one. The American Contact Dermatitis Society named it Allergen of the Year for 2018 because it acts as both a weak sensitizer and an irritant. It's in everything from moisturisers to toothpaste.

4. Propanediol — often marketed as a 'natural' alternative to propylene glycol because it can be derived from corn. The molecular structure is identical regardless of the source. Your skin reacts to the chemistry, not the marketing story.

Preservatives: The Price of Shelf Life

The paraben panic led manufacturers to switch to alternative preservatives. Many are worse than what they replaced.

5. Phenoxyethanol: A hotly debated preservative that I'm particularly sensitive to. It's believed to be a major trigger of contact dermatitis. The EU restricts it to 1% in cosmetics for good reason. That burning sensation when you apply certain products? Often this.

6. Benzyl Alcohol: A sensitizing ingredient produced by combining benzyl chloride with sodium hydroxide. Known irritant, especially problematic in eye products. If your eye cream is making your eyes water, check for this.

7. Sodium Hydroxymethylglycinate: Only permitted in maximum concentrations of 0.1%. That low concentration limit exists because it's a known irritant. It's a formaldehyde releaser, which explains the irritancy issues. Should always appear at the very bottom of an ingredients list. If it appears higher up the list, avoid the product.

8. Methylisothiazolinone (MI): The American Contact Dermatitis Society named MI Allergen of the Year for 2013 due to skin sensitization from dermal exposure. Studies show relapses occurred in 64% of patients with MI-induced allergic contact dermatitis, meaning once you're sensitised, it's incredibly hard to avoid. It's everywhere: baby products, bath products, makeup, hair care products, nail products, moisturizing creams, sunscreen and baby wipes.

Fragrance: The Sweet-Smelling Culprit

Synthetic fragrance is often listed as 'Parfum', a term that can hide hundreds of potential irritants (see my previous post for the full story).

Parfum can also disguise natural essential oils, some of which are pretty aggravating themselves. The two I'm most sensitive to:

9. Eucalyptus — gives products a sharp, fresh aroma but its antiseptic properties make it overly stimulating on skin. That tingly feeling isn't freshness - it's irritation.

10. Lemongrass — vibrant citrusy aroma that I love. My skin doesn't. Its high astringency aggravates delicate skin, and it's an emmenagogue so should be avoided during pregnancy.

The Bottom Line

Everyone's triggers are different. What sends my skin into meltdown might be fine for yours. But if you're dealing with unexplained reactions, persistent redness, or that tight, angry feeling after cleansing, start here. Check your products for these ten ingredients.

The good news? Once you know what to avoid, finding products that actually work becomes much easier. At Pai, we formulate without any of these ingredients because we know how devastating reactions can be. Every product is independently patch tested, even on sensitive skin, because we've been there too.

If you're struggling to identify your triggers, patch test new products first. Apply a small amount to your inner arm and wait 24-48 hours. Your skin will tell you everything you need to know. And if you're dealing with severe or persistent reactions, see a dermatologist. Some sensitivities need professional help to manage.

Remember: reading ingredient lists gets easier with practice. Soon you'll spot the troublemakers at ten paces. Until then? This list is your cheat sheet.