Section 01Why categories and not products
Product recommendations decay. A formulation changes, a line is discontinued, a size is repackaged, and a recommendation written last year points at something that no longer exists. More importantly, a product recommendation asks you to trust the recommender, whereas a set of criteria asks you to check the packaging yourself, which is a skill that keeps working.
So this publication assesses categories. Retinoids, vitamin C, exfoliating acids, sunscreens, azelaic acid, niacinamide. For each, we publish what a product in that category needs to demonstrate, and you apply it in whatever shop you use.
Section 02The criteria we apply to every category
- The active ingredient is named specificallyNot a family, a molecule. Retinol, retinaldehyde and retinyl palmitate are different things with different potencies, and a product that says only vitamin A derivative is telling you less than it could.
- A concentration is statedWithout one, a product cannot be compared with another, cannot be ramped deliberately, and cannot be escalated from. This is the single most common gap in cosmetic labelling.
- The packaging suits the ingredient's stabilityLight and air sensitive ingredients in clear jars are a formulation decision that works against the ingredient. Opaque, airless or small opening packaging is the minimum for retinoids and ascorbic acid.
- There is not a second irritant in the same productAn active combined with high denatured alcohol content, strong fragrance or a physical scrub is two problems in one bottle, and it removes your ability to identify which one your skin objects to.
- The product does not combine two actives you should control separatelyCombination products remove the ability to vary frequency independently, which is exactly what every ramp on this site requires.
- A period after opening is stated and is plausibleThree to six months for unstable actives. A two year open shelf life claim for L ascorbic acid deserves scepticism.
- The claims match what the ingredient doesA niacinamide product claiming to reverse wrinkles is describing a retinoid. Treat a mismatched claim as information about the seller.
Section 03Where these appear
Category specific criteria appear on the relevant protocol page rather than being collected here, because they are only useful next to the instructions for using that category. The pages carrying published criteria are listed below.
- Cosmetic retinoids
- Vitamin C products
- Salicylic acid products
- Alpha hydroxy acid products
- Azelaic acid products
- Niacinamide products
- The core three: cleanser, moisturiser, sunscreen
- Sunscreens
- Shaving setups
- Eye products
Section 04The commercial layer, stated in advance
The rule, written before any arrangement exists, so that it constrains us rather than describing us.
| Rule | Applies to |
|---|---|
| Criteria are published before assessment | Every category, without exception |
| Retailer links only on category assessment pages | Never on protocol steps or condition pages |
| Any commission is stated at the top of that page | Not in a footer, not in a sidebar |
| No individual product is recommended by name | The criteria are the output, not a product list |
| No brand may pay to be assessed or to change criteria | No exceptions, no sponsored categories |
| No affiliate link is live today | True as of this revision |
The reason for publishing this before any arrangement exists is that a disclosure policy written after the money arrives tends to describe whatever was already happening. Written first, it is a constraint. We would rather be held to it than trusted on it.
Section 05Categories we will not assess
- Prescription medicines. Those belong with a prescriber and a pharmacist, not with a publication applying packaging criteria.
- Devices, tools and energy based equipment. The outcome depends on the operator at least as much as on the device, and we are not in a position to assess either.
- Clinics and practitioners. We publish the questions to ask and the registers to check. We do not rank providers we have not assessed, and we are not in a position to assess clinical practice.
- Supplements. The evidence base for oral supplementation in skin health is inconsistent and the regulatory position is complicated. We would rather say nothing than say something thin.
Section 06Challenging an assessment
If you think a criterion is wrong, or that we have applied one inconsistently, write to us through the contact page with the specific page and the specific criterion. Criteria are published so that they can be argued with, which is the point of publishing them.