Articles
How this stuff works
Background pieces that the rankings lean on: label conventions, ingredient behaviour, and the difference between a cosmetic claim and a finding.
- Exfoliants AHA, BHA and PHA, chosen by how skin responds rather than by strength The useful question is not which acid is strongest. It is which one is soluble in the thing you are trying to reach.
- Actives Niacinamide by percentage, and where the extra stops helping Most of the published appearance work sits between 2% and 5%. Shelves are full of 10% and 12%. Those two facts are worth putting side by side.
- Labels What "dermatologist tested" legally means It means a dermatologist was involved. It does not say how many people, what was measured, or what the result was.
- Sunscreen Why the SPF on the label is not what your face gets SPF is measured at a thickness almost nobody applies. The gap between the tested dose and the real one is the largest unmarked variable in sun protection.
- Barrier Ceramides, cholesterol and fatty acids, and the ratio nobody publishes Barrier repair research is about a mixture of three lipid classes in proportion. Packaging is about one of them, because it has the best name.
- Retinoids How retinoids convert, and what each step costs you Retinol, retinaldehyde and retinoic acid are three points on one pathway. The percentage on the box only means something once you know which point you bought.
- Labels Reading an INCI list, and what the 1% line tells you Ingredients above a certain point are ordered by amount, and below it they are not. Finding that point is most of what label reading is.
- Method What a serum costs per use, and why almost nobody can tell you We tried to compute cost per application for nineteen products. One label made it possible. Here is what the other eighteen say instead.
- Labels Fragrance-free, unscented and clean are three different claims Two of them are about what is in the bottle. One of them is about nothing in particular.