If you have acne, you may have looked up “comedogenic” ingredients and taken note to avoid them. However, everyone’s skin is different, and it’s difficult to generalize the comedogenicity of ingredients.
First of all, acne can occur for different reasons. The most common reason is an occlusion of the pore, and that’s why it’s widely advised for acne-prone skin to avoid thick ingredients or oils that coat the pores. And while we’ve all heard brands say no “pore-clogging” ingredients, let’s delve a bit deeper into the meaning of a “clogged-pore.”
Before you can even see the pimple, a microcomedone or a whitehead forms underneath the skin and eventually becomes trapped by a natural seal. Underneath that occlusion, P acnes bacteria begins to consume your skin’s oil, and the comedone becomes inflamed. Having a naturally higher rate of oil production or even applying oil is known to compound and trap oil, and that’s what is known as comedogenic or “pore-clogging” (Chularojanamontri, 2014).
However, there’s another form of acne called hormonal acne, and this has little to do with what you’re putting on your face. So, just because you have acne doesn’t necessarily mean you should steer clear of occlusive ingredients.
Everyone has unique skin chemistry, and additionally, even though an ingredient is comedogenic on its own, this doesn’t mean it will be comedogenic once it’s put into a product like a serum (Wong, 2018). It also depends on the ingredients’ dosage. When you mix different things together, it changes the comedogenicity (Wong, 2018). For example, by itself, avocado oil is known to be comedogenic, but upon being mixed with alcohol or acid, it may not be. The Avocado Melt Retinol Sleeping Mask by Glow Recipe is a great example.
Avocado Retinol Sleeping Mask - $42
On top of that, studies that produce comedogenicity ratings don’t give us real insight into how these ingredients function once they’re put into skincare products. Did you know that the most common test for comedogenicity is done on rabbit ears (Draelos MD, 2006)? The comedogenicity scale ranges from 1 - 5, and ingredients are applied to the inner ear of the rabbit to determine its rating. The goal of the test is to see if any pores or comedones appear on the rabbit’s ear after application. Because rabbit ears are far more sensitive than human ears, and plus, they have larger pores, this is a very strange way to determine comedogenicity (Draelos, 2016). For example, mineral oil is said to be one of the most comedogenic ingredients ever, but this widely accepted presumption is based on the rabbit ear model test (Draelos, 2016).
Some comedogenic scales are done wiith human skin tests, but this test is used on people’s backs. Our back skin is very different from our face, and the participants normally have large pores. They swab the substance on the participants’ back, and they cover it with a bandage which also increases an ingredients penetration (Wong, 2018). This is not a duplication of a real-life situation like using a serum on your face.
Therefore, let’s take a closer look at comedogenicity myths and facts. What’s the truth about some of the most “pore-clogging” ingredients?
Coconut oil is a thicker oil, and many say that it’s absorbed poorly, it sits on top of the dermis, and it forms a film over the pore. Consumers are told to stray away from coconut oil because bacteria and dead skin cells will then fester under the film it creates, and likewise, cause your body to produce excess sebum and acne.
However, coconut oil is a rich triglyceride fantastic for removing makeup or applying (in a balm form) before a wash. Oil dissolves oil, and if coconut oil is washed off well, it can actually work against clogged pores.
Secondly, coconut oil has the potential to fight clogged pores since it consists almost entirely of medium-chain fatty acids (MCFAs). MCFAs have strong antimicrobial effects. More than 50% of the fatty acids found in coconut oil are MCFAs, lauric acid being the most notable (McDonnel, RD, 2021). To start with, lauric acid, by itself, is actually great for acne. Lauric acid can kill p acnes bacteria if the molecule is minimized and made small enough to sink into the pores.
Furthermore, coconut oil is made up of triglycerides. Triglycerides can be broken down by enzymes in our skin called lipases. When a triglyceride is broken down, free fatty acids are made (McDonnel , RD, 2021). Our skin gets benefits from free fatty acids after the lipases break them down.
On the other hand, coconut oil is a big molecule, and you have to have the right genetics to break it down thoroughly or to leave it on your skin without comegenicity (Widianingrum, 2019). As mentioned before, lipases or enzymes in our skin can break up triglycerides. Some of these enzymes are made by humans, but many of them are made by microorganisms living in the skin (Widianingrum, 2019). Most of these microorganisms live under your skin within your pores, and P acnes bacteria is actually the main microbe that produces lipases (Widianingrum, 2019). That’s one of the reasons we say protecting your skin’s “microbiome” is good! Contrary to popular belief, all P acnes bacteria do not need to be destroyed.
So ultimately, different cell turnover rates, different pore sizes, different microbiological populations, different immune responses will all determine whether or not coconut oil is truly “pore-clogging” or helpful for you. All in all, it's better for you to know your skin type and patterns than to memorize “comedogenic ingredients.”
Isopropyl myristate is another ingredient known to be comedogenic. It has a comedogenicity rating of 3. However, the first component of this ingredient is isopropyl alcohol, an antimicrobial agent, and the second component is myristic acid, a naturally occurring fatty acid often found in coconut oil too. When these two ingredients are combined, they create a very moisturizing emollient.
Because it’s used to lock in moisture and thicken products, isopropyl myristate can be a bit heavy for some skin types, and it can lead to pore-clogging. On the other hand, it also increases the penetration of ingredients, which can actually help clear pores depending on what is in the formula.
Essential oils like lemon and bergamot oil possess antibacterial and anti-inflammatory properties. They are also very fragrant. Many people like essential oils for this reason, but they are very unstable (Bae, MD, 2021). They are water-insoluble or poorly soluble, and they are prone to degradation upon exposure to high temperatures, oxygen, and light (Bae MD, 2021). These are really unfavorable characteristics when it comes to skincare.
Because essential oils are highly reactive to oxygen and light, they can degrade on your skin, cause photosensitivity (light sensitivity), and sensitization which can lead to inflammatory responses like acne (Bae, MD). So, while essential oils are sometimes called comedogenic simply because they’re oils, they are generally used sparingly. And most of the time, the molecules are small in size and not directly pore-clogging. So, essential oils can inadvertently clog your pores by causing an inflammatory reaction.
Take into account your skin type and your skin pattern before applying anything, and as always, apply your SPF!
Draelos, Zoe. DiNardo, Joseph. A Re-evaluation of the Comedogenicity Concept. 2006. https://www.sciencedirect.com/science/article/abs/pii/S0190962205046001
Heliyon.Antibacterial and immunomodulator activities of virgin coconut oil (VCO) against Staphylococcus aureus. 2019. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6817632/