Non-comedogenic

'Non-comedogenic' means a product is formulated to be unlikely to block pores and cause comedones — blackheads and whiteheads.

The important thing to know is that the term is not regulated. No authority defines it, no standard test is required, and a brand can print it on a product that has never been tested. It is a useful signal of intent, not a guarantee.

It is also not a property of an ingredient on its own. The old comedogenicity ratings came from tests on rabbit ears in the 1970s, which predict human reactions poorly. Coconut oil scores badly and causes problems for many people; others use it without trouble. Concentration and the rest of the formula matter more than any single ingredient's score.

In practice: treat it as a hint, not a promise. If a product breaks you out in the same places within two to three weeks, it does not suit you regardless of the label. If you are prone to congestion, introduce one new product at a time so you can tell which one did it.

'Oil-free' is a different claim, and also not the same as non-comedogenic.