SECTION 05ENTRIES 4LATEST 2026-07-02
The
ledger
Notes from the bench. Mostly about dose, method, and the specific numbers this category has decided not to print on the outside of the box.
SUBJECTS COVERED
SPFDOSEMETHODDOSE-RESPONSEFORMULATIONRETINOIDTOLERANCEAGEINGMODEL
A
Latest
2026-07-02
L-046′MINUTES
The number nobody publishes
Every sunscreen on earth is tested at 2 mg/cm². Almost nobody applies 2 mg/cm². The gap is the whole product.
SPFDOSEMETHODREAD
B
Archive
3 ENTRIES
- L-032026-05-19
Against the actives arms race
Ten percent niacinamide is not twice as good as five. The dose–response curve flattens and the complaint rate does not.
DOSE-RESPONSEFORMULATION5 MIN - L-022026-03-08
Retinisation is not a result
The flaking at week three tells you a retinoid is present. It tells you nothing about whether it is working.
RETINOIDTOLERANCE4 MIN - L-012026-01-14
What thirty actually changes
Not a cliff. A set of slopes that were already running, becoming visible at the same time.
AGEINGMODEL7 MIN