The Ultimate List of Pore Clogging Ingredients To Avoid

by Samantha

Much of the information on what acne-causing ingredients are otherwise popularly labeled as “comedogenic”. It would be nice if we could just get an acne vaccination , but in reality, taking care of our skin means paying a little extra attention to checking if there are acne-causing ingredients in our products. 

In this article, we will review what pore-clogging ingredients are, share a list of the comedogenic rating of the common skincare ingredients, and explain what it all means for those with acne-prone skin.

While not everyone’s skin will respond the same to every ingredient, and not all types of acne are related to pore-clogging ingredients, there are some general rules to follow when looking for skincare products for acne-prone skin types!

The list of acne-causing ingredients is HUGE , but here is a list of top 11 acne-causing ingredients to avoid:

1. Cocoa butter
2. Coconut butter 
3. Acetylated lanolin alcohol
4. Laureth-4
5. Myristyl myristate
6. Isopropyl isostearate
7. Isopropyl linoleate
8. Cetyl acetate 
9. Cetearyl alcohol + ceteareth-20
10. Lauric Acid
11. Oleth-3

What does a comedogenic rating mean?

A comedone is a clogged hair follicle (pore), created from keratin (skin debris) and sebum. Therefore, something is considered comedogenic if it has a tendency to block pores and promote the formation of comedones. The higher the comedogenic rating, the more likely it can clog pores and cause acne.

This factor helps us to determine if it is an acne-causing ingredient. Ingredients are ranked on a comedogenic scale:

0 – non-comedogenic

1 – slightly comedogenic

2-3 – moderately comedogenic

4-5 – highly comedogenic

If true, comedogenicity would be an important consideration in the development of products applied to the skin, especially facial skin which is more susceptible to comedones. 

But keep in mind this rating was developed in 1972 by putting high concentrations of these single ingredients on rabbit’s skin. We’ll touch more on that later. 

List Of Comedogenic Ingredients with their Pore Clogging Rating

So, here is a fairly extensive list of ingredients and their comedogenicity ratings based on the original models.

Pay particular attention to the 4-5 ratings, and only if they’re within the first few ingredients of a product.

Keep in mind that just because something is low on the comedogenicity scale doesn’t mean it won’t be problematic for your skin and vice versa.

Guide: 0-1 Not pore-clogging.  2-3 Moderately Pore Clogging.  4-5 Highly Pore clogging, best to avoid especially if they are near the top of the ingredient list. 

How Ingredients Were Determined If They Are Comedogenic?      

Originally, animal models were used to determine the comedogenic potential of raw materials, with the assumption that the finished formulations containing these ingredients would also be comedogenic.

In 1972 Kligman and Fulton applied substances to the inner ear of rabbits and determined that certain acne-causing ingredients for rabbits were capable of forming comedones in humans, as well. But rabbit ears are not human ears.

Rabbit ears are more sensitive than human facial skin is, which is likely why they were chosen: they would, therefore, produce faster, more inflammatory results. One pervasive example is petroleum jelly, which was deemed highly comedogenic in the original study but has since been changed to non-comedogenic. Kligman even followed up , stating,

“Serious controversies have sprung up regarding the reliability and relevance of the rabbit ear model […] 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.”

In a 1982 study following the rabbit ear model, test substances were applied to the backs of human patients with large follicles and occluded by covering the area with a bandage.

Again, we run into the problem that this isn’t necessarily a realistic scenario, though it is convenient for testing. Back skin is very different from facial skin, especially when the patients also have particularly large follicles, as they did in the study. Like the rabbit model, this could easily produce false-positive results. The small sample size is also a major concern, as it is hard to extrapolate the findings of so few people.

The 3 major concerns from the studies on acne-causing ingredients are:

1. The other ingredients present in the formula and the way it is formulated.

It’s important to note that just because a product contains comedogenic ingredients, does not mean that the finished product will necessarily be comedogenic. Similarly, a finished product can end up being more comedogenic than the ingredients themselves. It is well understood in the scientific community that substances can become non-comedogenic when sufficiently diluted.

When applied at 50-100%, some ingredients receive a comedogenic rating of 4-5, but when diluted to only 25%, the comedogenic rating can drop to 1!

Other than concentrated, medicated products, most product ingredients are diluted with water, leaving anything else well below 25%, which would, therefore, render the ingredient in that formula non-comedogenic.

2. The concentration, duration, and circumstances under which these ingredients were applied.

 For example, in all cases, these ingredients were applied in their raw form, which is vastly different from the finished product that you would be applying to your face.

These applications have low external relevance, meaning their results may not apply well to real-world circumstances. There are some instances (such as coconut oil, typically applied undiluted) which still received a high rating of 4. Yet some people can still use it with no problems, which leads me to my third concern.

3. Comedogenic ratings tend to be blanket statements.

Kligman, from the original rabbit ear assay, even stated that “Substances deemed to be strongly comedogenic by some are declared by others to be innocuous. Reviewers have not failed to notice the high frequency of strikingly contradictory results .”

This might be due to the simple fact that our skin is not all the same – the exact same conditions applied to two different individuals can easily yield very different results.

Products That Are Great For Acne

All Clear Mint Cleanser

The Defender SPF 50 with Peptides

Will checking an ingredient’s comedogenic factor help me?

Many dermatologists condemn the models as entirely useless in providing information on which ingredients are and are not comedogenic, while others still rely on the comedogenicity scale heavily. Despite this, we still know there may be some relevance for people who are prone to cosmetic acne, particularly if an ingredient scored very high (4-5) on the comedogenicity scale.

To put it bluntly, if you’re prone to having acne and you have particularly oily skin, checking the comedogenic rating for ingredients will probably be beneficial to you.  

Do You Have Acne Caused By Makeup Or Skincare?

Acne cosmetica is a type of acne that is caused or aggravated by cosmetics that contain certain acne-causing ingredients. One study in 1976 used the rabbit model to formulate a “non-comedogenic” cosmetic formulation; it’s use in acne-prone women reduced the rate of acne from 25% to less than 5%.

This is promising for acne-prone individuals when using the list below to seek out products with fewer acne-causing ingredients. However, this study did not include individuals who are not acne prone, and so the results cannot be extrapolated.

Despite this, more companies are beginning to realize the importance of a product that doesn’t promote the formation of comedones for everyone, not just acne-prone individuals. So, while there are still some culprits on the market, there is promise on the horizon!

Keep in mind that even our hair products can be comedogenic, and cause acne (particularly along our hairline).

Other Ingredients that can cause acne if you are acne prone.

Even though silicones are a 1 on the comedogenic scale they can still cause acne  especially if you are already acne prone.

If you suspect silicones area breaking you out, the forms of silicone include dimethicone, methicone, trimethicone, cyclopentasiloxane, and cyclotetrasiloxane.

Silicones are used because they create a protective barrier around skin, and if you aren’t acne prone it usually won’t cause issues.

If you have acne, this thick occlusive layer from silicones means the oils and acne causing bacteria are now trapped on the skin which can lead to more breakouts. Although they aren’t comedogenic, these can lead to acne and may potentially clog pores especially if the silicones are not thoroughly washed off. 

The bottom line is, just because a product contains a potential pore-clogging ingredient, doesn’t mean the product itself is comedogenic; particularly if the ingredient is very low on the ingredients list. If there are several highly comedogenic ingredients high up on the ingredients list, it’s probably a good idea to stay away from it if you’re acne-prone.

What Do I Do About Clogged Pores?

Thankfully, even if a product you tried out does end up causing clogged pores and a breakout, there are things you can do to expedite your skin’s recovery!

As mentioned, there may be ingredients that are non-comedogenic, which should still be avoided for other reasons (health and skin-related), but that’s another topic for another day. For more tips on picking the best products for your skin, see our post on Minimalist Skincare , or our helpful guide on Finding the Right Product for Your Skin Type .

You don’t need to go through your current skincare products and scan the ingredients over with a fine-tooth comb to determine what ends up in the garbage bin – if they’re working well for you, that’s all that matters.

It also doesn’t mean you should completely discount buying a new product just because it has potentially acne-causing ingredients on the list (unless you are acne-prone and it’s one of the first few ingredients, but even still). Overall, what matters most is a good product formula, and most products geared toward acne will be a safe bet