Comedogenic ingredients: when is there cause for concern?

Comedogenicity, or pore-clogging, occurs when a plug of cells, sebum, and air-sensitive cosmetic ingredients oxidize and harden in a pore. The top of the plug darkens forming what we call a ‘black head’ or open comedone. Usually associated with acne and clogged pores, comedones can form in any skin type, including the driest of the dry. This is why it’s best to know your way around the world of pore-clogging ingredients.  

For instance, just the presence of a pore-clogging ingredient doesn’t indicate the product will clog your pores. This may come as a shock to many of today’s estheticians, dermatologists, and influencers, but, based on clinical and histological studies performed way back in the Sixties, it’s true. Here’s other points to consider:

1. How long does the product stay on your skin? The shorter the amount of time, the less likely your pores will plug up. So a cleanser with isopropyl myristate (probably the most comedogenic ingredient around) that stays on your skin for under a minute won’t clog your pores, while a moisturizer with the same ingredient will most likely be a problem after a few weeks of use.
2. How much of the comedogenic ingredient is in the product? If a highly comedogenic ingredient is one of the first three-to-five to occur in the product’s ingredient list, it’s more likely to cause clogged pores.
3. Are there other comedogenic ingredients in the product? The more pore-cloggers in the product, the more likely your pores will clog.
4. Where are you applying the product? Not all areas of the skin are prone to comedones. Most likely to clog? Pores on the face, back, and legs. Least likely? Areas on the arms, hands, feet, front of torso, chest, neck, buttocks, and around the eyes from just under the brow to the inside top of the cheekbones just under the eye (aka: the periorbital area).
5. How long and/or how frequently will you be using the product? It takes several weeks to months of consistent use for comedogenic ingredients to stick in pores and oxidize. If you’re applying a product once a week - or only using it for a few weeks - the product is safe even if it’s loaded with pore-cloggers.

What’s the best way to tell if a product will clog your pores? Look for a ‘non-comedogenic’ claim on the package or in advertisements. In order to make such a promise, the company must perform a standardized test on the finished formula to determine if it causes clogged pores. 

But if you want to do it the hard way by checking every ingredient in the product, here’s a list of highly, moderately, and mildly comedogenic ingredients, as well as one of non-comedogenic ingredients that are often thought to be comedogenic. 

Highly Comedogenic (5)

Acetylated lanolin alcohol

Ascorbic acid (oxidized)

Butyl stearate

Cocoa butter

Coconut butter

Coconut oil

Decaglyceryl decaoleate

Flax oil (aka: linseed oil)

Isocetyl stearate

Isoparaffin C9-11

Isopropyl isostearate*

Isopropyl lanolate*

Isopropyl linoleate*

Isopropyl myristate*

Isopropyl neopentanoate*

Isopropyl palmitate*

Isostearic acid

Lanolic acid

Linseed oil

Myreth-3 myristate

Myristyl lactate

Myristyl myristate

Octyl palmitate

Octyl stearate

Oleic acid (in natural oils)

Oleyl alcohol

Peach kernel oil

PPG-2 myristyl propionate

Squalene

Sweet almond oil

Wheat germ oil

* Isopropyl ester series

Moderately Comedogenic (3-4)

Butyl stearate

Decyl oleate

Ethoxylated lanolins (ex: laneth-10)

Grape seed oil

Hexylene glycol

Isostearyl alcohol

Isostearyl neopentanoate

Laureth-4

Lauric acid

Linoleic acid (Omega-6)

Linolenic acid (Omega-3)

Most D&C red pigments

Myristic acid

Myristyl lactate

Octyl palmitate

Octyldodecanol

Palmitic acid

Peanut oil

Sesame oil

Sorbitan oleate

Soybean oil

Tocopherol

Mildly Comedogenic (1-2)

Anhydrous lanolin

Argan oil

Ascorbyl palmitate

Avocado oil

Behenic acid

Black current oil

Borage oil

Capric acid

Caprylic acid

Castor oil

Ceramides

Corn oil

Crisco™

Evening primrose oil

Glyceryl stearate

Lanolin

Lanolin alcohol

Lanolin oil

Lauryl alcohol

Mineral oil, cosmetic grade

Olive oil

Peanut oil

Petrolatum (cosmetic grade)

Retinyl palmitate

Safflower oil

Shea butter

Stearic Acid

Sunflower oil

Non-Comedogenic (0)

Allantoin

Ascorbic acid (non-oxidized)

Beeswax

Behenic acid

Butylene glycol

Candelilla wax

Carbomer

Carmine

Carnauba wax

CBD

Cetyl palmitate

Cyclomethicone

Cyclopentasiloxane

Dimethicone

Emulsifying wax

Ethanol

Glycerin

Hemp seed oil

Iron Oxides

Isopropyl alcohol

Jojoba oil

Kaolin

Lecithin

Mineral oil, USP*

Octinoxate

Octyldodecyl stearate

Octisalate

Oxybenzone

PABA

Panthenol

Parabens

Paraffin

Petrolatum, USP

Polysorbates

Propylene glycol

Propylene glycol dicaprate/dicaprylate

Retinol

Rose hips seed oil

SD alcohol

Silicones

Sodium hyaluronate

Sodium PCA

Sorbitol

Squalane**

Tea tree oil

Titanium dioxide

Tridecyl stearate

Tridecyl trimellitate

Water

Zinc Oxide

Zinc stearate

* While not a comedogen, mineral oil can exacerbate the pore-clogging effects of comedogenic ingredients in the product

** Hydrogenated from squalene, a highly comedogenic ingredient