Azelaic Acid
Learn how azelaic acid products differ, what prescription labels cover, and what research says about post-acne marks.
Read the ingredient guideA little less label confusion.
Explore ingredient roles, make sense of labels, and put the whole formula in context.
Ingredient literacy
Understand the ingredient. Consider the whole product.
From glycerin to retinol, explore what familiar skincare ingredients do, the questions readers ask, and where the evidence has limits.
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The ingredient library
12 ingredient guidesLook past the front label.
What it does, what the evidence supports, and what to check before you buy. Search a name from your label or browse by its role.
12 ingredients
Ceramides
Understand ceramides in moisturizers, the evidence for dry and eczema-prone skin, and why the complete formula matters.
Read the ingredient guideGlycerin
What glycerin does in a moisturizer, how it differs from glycolic acid, and why a simple cream may be all you need.
Read the ingredient guideGlycolic Acid
What glycolic acid does for skin texture, why pH matters alongside percentage, and the sun-sensitivity precautions to know.
Read the ingredient guideHyaluronic Acid
Learn what topical hyaluronic acid does, how sodium hyaluronate fits in, and why a hydrating serum is different from a filler.
Read the ingredient guideNiacinamide
What niacinamide can do for skin, what its studies actually tested, and how to decide whether to add it to your routine.
Read the ingredient guidePetrolatum
Learn how petroleum jelly reduces water loss, when it can help dry skin, and why full-face slugging is not for everyone.
Read the ingredient guideRetinol
Understand retinol versus other retinoids, what wrinkle research shows, and the irritation and pregnancy precautions that matter.
Read the ingredient guideSalicylic Acid
Understand salicylic acid strengths, acne Drug Facts labels, wash-off versus leave-on products, and how to avoid an overly harsh routine.
Read the ingredient guideTitanium Dioxide
Understand titanium dioxide and CI 77891 on labels, mineral sunscreen protection, and why the product form matters in safety questions.
Read the ingredient guideVitamin C
A practical guide to vitamin C serums, ascorbic acid and derivatives, the limits of the research, and choosing a place in your routine.
Read the ingredient guideZinc Oxide
Learn what zinc oxide does in sunscreen, how to read SPF and broad-spectrum claims, and why a higher zinc percentage is not a protection score.
Read the ingredient guideNo ingredients match.
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Research drafts · Independent medical review pending. An ingredient’s role does not tell you how well a finished product will suit your skin.
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