The 1% Line

Cosmetic labelling rules require ingredients to be listed in descending order of concentration only down to one percent. Below that, a manufacturer may list whatever remains in any order it likes. The 1% line is the industry's informal name for the place where that obligation stops.

The consequence is that reading down a list tells you progressively less. Water at the top really is the largest component. By the time you reach the tail, the order is arbitrary: a peptide at position twenty-two might be present at 0.9% or at 0.0001%, and the ingredient printed after it might be present in greater quantity.

Finding the line is guesswork, but there are markers. Preservatives work at fractions of a percent, so phenoxyethanol, sodium benzoate or ethylhexylglycerin usually sit at or below it. Gums and carbomers thicken at a few tenths of a percent. Fragrance and colourants are conventionally printed last whatever their level. Anything appearing after the first of those is in undeclared territory.

This is why “contains niacinamide” and “contains enough niacinamide” are different claims, and why a percentage a brand chooses to publish is worth more than a position in a list. The reverse inference fails too: plenty of ingredients do their job well below one percent, so a low position is not by itself evidence of a token amount.