I continuously come across natural skincare articles on the internet written by well-meaning people who want to teach you to use natural skincare and avoid synthetic ingredients. They say things like:
- Your skin absorbs 60% of everything you put on it.
- Your skincare is filled with ingredients that are bad for you.
- You need to avoid all of these preservatives in your skincare.
- You should be buying skincare products that don’t contain any chemicals.
All of these statements require some qualification and in some cases (the 60% absorption rate in particular) they are complete internet myths that continue to do the rounds on websites written by people who use other people’s blogs to research what they write.
The other one I hear a lot is about needing to let our skin breathe. Let’s contemplate that statement for a minute.
Does your skin have little mouths gasping for air?
When we breathe, we move air in and out of our lungs. We need oxygen to be delivered to different parts of our body and to release energy. We also breathe in order to get rid of excess carbon dioxide in our bodies and to help move blood around the body. It’s an amazing part of our human physiology and we would die without being able to breathe.
But does the human respiratory system include the skin? Of course not. The skin is the body’s largest organ and makes up about 15% of our body weight. It does lots of amazing things like hold all our internal organs together but it doesn’t play an active role in helping us breathe. The skin can absorb some oxygen under the right circumstances but that isn’t helping it “breathe”.
I’m always amused when I read people saying that our skin breathes, because I have a mental image of thousands of little mouths opening and closing on my skin, gasping for breath if I dare to put a moisturiser on them. Mammals don’t breathe through their skin, apart from this awesome tiny Marsupial mouse called the Julia Dunnart which is too weak to inflate its lungs when it is first born, so it breathes through its skin instead until it leaves its mother’s pouch.
You might have heard the urban myth about the actress in Goldfinger (1964) having died from being painted with gold paint because her skin couldn’t breathe. At the time, the film studio had doctors standing by to make sure Shirley Eaton wasn’t overcome by the effects of being painted with gold paint, despite having left a large unpainted patch on her abdomen. The idea of clogging your pores with paint effectively stopping you from being able to breathe was a plausible scientific explanation at the time, but we now know better.
What does the cosmetics industry mean by letting your “skin breathe”?
They’re trying to tell you that their product won’t clog your pores and will leave your pores open – to “breathe”. Saying “our products help your skin breathe” always sounds better than saying “our products won’t clog your pores“. I understand what they’re trying to say, it’s just an unfortunate way of explaining the benefits of their product.
When a product or ingredient is known to block pores, it is also called “comedogenic”. A comedo is a blocked hair follicle in the skin – a spot or a pimple. Again, the internet is filled with helpful lists of which ingredients are comedogenic and which aren’t. What they don’t tell you is that this list is based on research done in the 1950s where researchers tested products on… rabbit ears. I think regardless of your stance on animal testing and the cosmetics industry, we’re all likely to agree that our skin probably behaves quite different to that of a cuddly rabbit and its cute fluffy ears.
So when you apply a skincare product and you let your skin “breathe”, you are effectively using ingredients that don’t cause pimples. Now let’s have a look at one of the most maligned products in the world of skincare – mineral oil.
Does mineral oil form an occlusive layer on your skin?
Firstly, a caveat from me – I don’t use mineral oil. I worked as an environmental scientist in the oil industry for years and am not a big fan of petroleum-based skincare products for various environmental reasons and also the fact that I love using plants for beauty. However, I don’t use my blog as an opportunity to jump up and down about non-plant based skincare (yes, I am aware that fossil fuel deposits originally came from plants, smarty pants) because I’m much more interested in researching the benefits of all the wonderful botanical extracts out there in the world.
However, the internet is full of articles from people telling you that mineral oil / paraffin oil / Paraffinum Liquidum will form an occlusive layer on your skin and… stop it breathing. They’ll tell you that mineral oil has large molecules that don’t penetrate the skin and sit on your’s skin surface, much like a layer of cling film trapping sweat and bacteria beneath it. Is this true?
A study in 2011 compared mineral oil with jojoba oil, almond oil, avocado oil and soybean oil. The study found that none of the oils penetrated the skin further than the top 2-3 layers of corneocytes – the upper layers of cells in the upper layer (stratum corneum) of the upper layer (epidermis) of the skin. Only almond oil and soybean oil made it to the third layer, the other oils either sat on the skin’s surface or made it to the first two layers of cells.
In other words, vegetable oils act in the same way as mineral oil – forming a layer on top of the skin. The main difference mentioned by the authors of the study is that vegetable oils are similar in composition to skin lipids so they are taken up by the skin through enzymatic decomposition while mineral oil is not metabolised. Furthermore, many vegetable oils contain components such as triglycerides, flavonoids, phytosterols and tocopherols which provide additional benefits for your skin whereas mineral oil is very simple molecule made of only two atoms – carbon and hydrogen.
Oils applied to your skin trap water underneath them and make your skin feel temporarily softer and smoother. They provide moisture to the top layers of the skin. There is no difference in this process regardless of whether you use mineral oil or vegetable oil. Nonetheless, certain types of oils might be more conducive at blocking pores than others. It’s worth experimenting with different oils if you find that you break out every time you use one.
But one thing is certain about ALL types of oil – and all other skincare ingredients for that matter – they are not stopping your skin from breathing.
Which oils cause you to breakout? Leave me a comment below and share your story!