What are Comedogenic Ingredients in Skin Care Products?
By Cynthia Bailey MD.
What are comedogenic ingredients in skin care products? Many have struggled with this question at some point in their lives. Acne impacts us and we want to know how to control it. The first place most people look is at their skincare. If you’ve gone ‘down an internet rabbit hole’ studying the subject, you know the answers are confusing.
How Do You Know If a Product Will Cause a Breakout?
It's not easy. You need to read labels, learn what ingredients are notorious for being comedogenic, try to avoid them and test products on your skin carefully when you can't figure it out.
What is a Comedo?
A comedo is a widely dilated pore (which is a hair follicle whether there is a hair in it or not) filled with keratin debris composed of dead skin cell matter, bacteria and sebum. A comedo can be open, in which case the tip of the opening is topped with a blackened mass of dead skin debris and it is called a 'blackhead'. A closed comedo has skin covering the opening. A closed comedo may be inflamed, in which case it is a pimple and it may be topped with a pustular white head. A closed comedo may also be non-inflammatory and appear like a small white bump.
What Exactly Are We Calling a Breakout or Acne?
Obviously, a big red pimple with a whitehead counts. A huge and hard plug of a blackhead in a pore counts. What about clogged pores without a hard plug? Or an increased size and dilation of pores without stuff visible in the pore? Does that count? What about deep and painful acne cysts that never come to the surface? Is that part of the acne discussion regarding skin care products that can break you out? Not really. The pores are the size that they are and don’t change much. Deep cysts are triggered by internal causes and not products.
Do You Head Straight for Products Labeled Non-Comedogenic Or Non-Acnegenic if You Have Acne?
If only it were that simple! Even the dermatology profession struggles with these labels. The potential for an ingredient to actually break you out is heavily impacted by the overall product formulation including the concentration, other ingredients in the product, proper usage, and how acne-prone your skin is. Infinite variables!
Definitions and Perspective on Comedogenicity
A comedogenic ingredient causes cells to stick together, causing a blackhead. The concept of skincare products causing blackheads started in the 1970s and 80s. Some of the first scientific studies happened on bunny ears and involved testing specific ingredients alone. Now humans are used. Testing is often done on the back and how the assessment is made varies.
Acnegenic is a term you will see used. It indicates whether something can cause a general worsening of acne.
What is a clinical use test for comedogenic ingredients?
A clinical use test is where individuals use a product under normal conditions for several weeks and are then evaluated for blackheads or pimples. This is the most meaningful way to determine if a product is compatible with a person’s skin. One can test on a small area of facial acne-prone skin, or even on non-facial skin such as the chest or back. These areas contain a high density of pores with oil glands.
What is cosmetic acne or acne cosmetica?
Cosmetic acne is the term used by dermatologists to describe acne caused by skincare products. It was first described by French dermatologists in the 1940s. They reported on “brilliantines and hair pomades causing flare-ups on the temple and forehead facial regions.” The blackheads looked normal and this eventually led to research and tests, rabbit ears, lists of ingredients to avoid, and a lot of misunderstanding ensued (my opinion). Our entire understanding of acne has changed in the past decade or so. Acne is now considered an inflammatory condition, not simply a circumstance limited to blackheads, too much sebum, and bad bacteria.
Ingredients to Avoid if You are Acne Prone
This list is from the original work on bunny ears surrounding comedogenicity and pore irritation. Take it with a grain of salt though. Acne is not a simple cause and effect relationship. Still, some ingredients are notorious triggers of acne. These include:
- lanolins (acetylated lanolin alcohol, PEG 16 lanolin)
- lauric acid
- cetyl acetate
- ethylhexyl palmitate/octyl palmitate
- isopropyl isostearate
- isopropyl linolate
- isopropyl myristate
- myristyl myristate
I also recommend that if you have acne-prone skin, you should avoid thick, greasy, or waxy products. They seem to be more consistently problematic for my acne-prone patients.
I’ve practiced dermatology for 30 years and I’ve seen many acne-triggering variations in my patients that go beyond products. These variations include: eventual changes in skin, seasonal/climate changes, T-zone versus non-T-zone, stress, hormones, sweat, wearing clothing that might block glands or rub oil on your skin, and changes in complexions with age.
The bottom line is the issue of acne and ingredients is NOT simple. I always recommend we watch, wonder, and learn when we have acne theories. We also carefully test products on skin when we are worried that they might trigger a break out.
How to Test a Product to See if it will Cause Acne
Do a clinical use test. Choose an area where a pimple won’t ruin your complexion. Add the product to your skin care routine and wait for at least 2 weeks. Look for blackheads, pustules, and at the general size of your pores. If it looks good, then consider doing split skin comparisons by using the new product on just one side of your face to gauge a difference.
If you don’t want to test the product on your face, use non-facial skin such as the chest or back, which are also acne-prone. Again, apply the product to a small area of skin for at least 2 weeks. If the results are positive, consider progressing to a limited area on your face and then to split face.
What Should You Be Doing to Help Control Acne?
Diet and smart lifestyle changes make a difference. Get those in order as best you can to fight acne. Click here to learn more about diet and acne.
My Diet, Lifestyle and Acne Rx Summary:
- Foods that worsen acne: cow dairy products, bad fats, high carbs, and sugar diets
- Foods that help fight acne: Whole foods including real fruits and veggies, beans, nuts and whole grains.
- Get rest, exercise, try to create a balanced schedule for stress and rest.
Best skin care options that are proven to help acne include:
Benzoyl peroxide: best in 2.5% concentration which works as well as higher concentrations with less risk of irritation.
Salicylic acid: penetrates oily pores to loosen blackheads.
Glycolic acid: loosens pore-clogging debris.
Retinoids: options include prescriptions such as tretinoin or non-prescription retinol.
If you have Pityrosporum Folliculitis type of acne, wash with pyrithione zinc. This is a time-honored remedy for this type of yeast acne.
Acne Skin Care Routine to fight open comedones (aka blackheads):
Morning Acne Skin Care:
CLEANSE and CORRECT acne with Foaming Acne Treatment Cleanser. The glycolic acid and salicylic acid help clean pores deeply as well.
CORRECT acne forming bacteria and blackheads with Benzoyl peroxide 2.5% lotion.
HYDRATE skin to prevent dryness with my Daily Face Cream for Oily to Normal Skin. This facial moisturizer has been put to the test by thousands of my acne-prone patients and we have found that it does not aggravate acne-prone complexions.
Get all three acne-fighting products in my Ultimate Acne Solutions Kit.
PROTECT skin from UV which can lead to brown scars and marks with Sheer Strength Pure Mineral Matte SPF 50+ Sunscreen. It is tinted to hide complexion flaws and the oil-absorbing matte base helps control shine.
Evening Acne Skin Care:
CLEANSE and CORRECT 'fungal' acne (Pityrosporum folliculitis) with Calming Zinc if you have yeast acne. Or use the Foaming Acne Treatment Cleanser.
CORRECT acne and blackheads with Retinol Night Cream which also helps to heal and prevent acne scars.
HYDRATE with the Face Cream for Oily to Normal skin.
Back and Chest Acne Skin Care to Fight Comedones and Pimples
CLEANSE and CORRECT acne and blackheads in one step with my medicated Body Acne Kit.
Fulton, James E, Comedogenicity and irritancy of commonly used ingredients in skin care products, J. Soc. Cosmet. Chem., 40, 321-333 Nov/Dec 1989
Draelos Zoe Diana, DiNardo Joseph C, A re-evaluation of the comedogenicity concept, JAAD March 2006, 54 (3) 507-512
Kircik Leon H, Advances in the Understanding of the Pathogenesis of Inflammatory Acne, J Drugs Dermatol. 2016: 15(1 Suppl 1):s7-s10