Cited skincare — every flag names its source, no upsell.
Me

Methylparaben

Methylparaben

One of the longest-studied preservatives, used in tiny amounts to stop bacteria and mold.

What it does

Brands moved to 'paraben-free' in the 2010s after hormone headlines; regulators in the US, EU and Canada still allow it.

The evidence, graded

moderateFragrance, essential oils, denatured alcohol and certain preservatives (methylisothiazolinone, the formaldehyde-releasers) are the usual suspects on sensitive skin. In the patch-test data read here — patients whose dermatitis was linked to a cleanser — the preservative quaternium-15 topped the list at 11.2% and fragrance mix I came fifth at 7.7%. Test a new product on a small patch of skin before you use it on your face.Warshaw 2018 · Dermatitis ↗

Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.

Pairs worth knowing

Browse all 1238 ingredients — grouped by what they do, each with whatever evidence we can cite.

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