Comedones are a form of acne caused by clogged pores.
- Comedogenic and irritancy ratings don't usually tell the whole story.
- They can be a useful source of information about an ingredient - and it's reasonable to take them into consideration when evaluating a formulation.
Comedogenic ratings
Comedogenic ratings were designed to measure the likelihood of an ingredient to cause comedones.
The comedogenic rating system is numbered 0 - 5.
A 0 on the scale means an ingredient has no chance of clogging pores. On the flipside, an ingredient with a rating of 5 is very likely to clog pores.
Drawbacks
The truth is, comedogenic ratings shouldn't always be taken for face value.
- The original test from 1972 was done on rabbit ears. Rabbit ears are more sensitive than human skin. They also have naturally large pores.
- There is limited human testing.
- Individual Ingredients vs. Entire Formulation
Comedogenic ratings are accounted for an ingredient, but not the entire product.
Why does this matter? Our skincare products are made up of many ingredients that all play a role. The comedogenic ratings of an ingredient is affected by the other ingredients.
4) Uniqueness of your skin
Dermatologists and skin experts all agree the chemistry of your skin plays a role in comodone creation. While an ingredient may clog pores for others may not be true for your skin.
The doctor who invented comedogenic ratings, Dr. Albert Kligman, has previously stated:
One cannot determine from a reading of the ingredients whether a given product will be acnegenic or not. What matters solely is the behaviour of the product itself
