Much maligned ingredients: Mineral oil (part 2)

A lot of the concerns about mineral oil relate to occlusion. (One quote is that it "coats the skin like plastic, clogging the pores".) If you've read any tiny bit of this blog, you know that occlusion is a good thing that helps reduce transepidermal water loss, and that mineral oil isn't the only thing that causes occlusion. Great things like our butters, heavier oils, silicones, and allantoin help to trap that moisture against our skin, and we want that! To use the words "coats the skin like plastic"...well, those words are just inflammatory. We wouldn't say that about mango butter, would we?

As a note, studies have shown that mineral oil prevents transepidermal water loss about 170 times better than olive oil. Olive oil is a good moisturizer, but I wouldn't call it a fantastic occlusive - not like the butters - but it's still a significant result! Its sister product - petroleum - reduces TEWL by 98%, which makes it the best occlusive ingredient out there.

Does mineral oil clog your pores? No. It's non-comedogenic, which is why we see it in a lot of moisturizers. It offers emolliency without clogging pores, and those of us with acne prone skin can actually benefit from using it in place of vegetable oils that do penetrate the skin or pores. (Click here for a summary of a good study or click here for another good study.) 

Is mineral oil absorbed by your skin? No. Mineral oil forms a layer on top of your skin, which is why it's a great occlusive ingredient. (One blogger I read claims it forms both the plastic film and sinks into your skin, and can sink into the skin of others if you touch them. Second hand mineral oil? How does that make any sense?) 

Is mineral oil safe for sensitive skin? Yes. You'd be amazed at how many sites I read that claim it will irritate skin, but, in fact, it is probably a better choice for sensitive skin than most of the oils we use. It doesn't contain proteins or polyphenols or phytosterols or other things that could set off reactions in sensitive or allergic skin types. 

Does mineral oil cause build-up on your hair or refuse to be removed? No. It is a great emollient for your hair, creating a barrier between the strands and the outside world which will reduce friction (and we know that friction is one of the main ways we damage our hair). It is easily removed with gentle surfactants.

Does mineral oil cause cancer? No. Any of the studies you see linking mineral oil to cancer are about industrial mineral oil - which is easily contaminated by other things - not cosmetic mineral oil. 

So does mineral oil offer any benefits to the homecrafter? I think it does...

• it's non-comedogenic;
• it's occlusive;
• it guarantees consistency in our products;
• it's inexpensive; and 
• it won't go rancid, so our products can have really long shelf lives.

So why don't I use mineral oil and why haven't I written about it on the blog? 

I have used it, and I like it in a moisturizer for my acne prone skin to offer moisturizing without break-outs, especially during the winter when I need some serious occlusion (and cocoa butter will make me break out like silly). I also use it in the form of holly oil (which contains mineral oil) as a very light, non-staining massage oil for my really sore back days. 

As an aside, it's interesting to see the glowing reports and write-ups about holly oil, which contains a very light mineral oil, when mineral oil gets such a bad rap! It's the same stuff! 

I don't use it a lot in my products because are so many amazing oils and esters available that offer incredible benefits - like olive oil with its great polyphenols, phytosterols, and hygroscopic abilities, to name just one - and I prefer to use oils that work as multipurpose ingredients. 

Plus, mineral oil can feel really greasy! I need about 5% IPM or a bunch of less greasy feeling esters to reach an acceptable level of oiliness in my products. (And I like my products on the greasy side, so you know it must be really greasy!) 

I haven't written about it on the blog because I really don't feel like defending my ingredient choices to the people who want to deride me for using mineral oil. I posted something somewhere once that I actually like it in a moisturizer, and I had to spend the rest of the time defending my choice with people who simply didn't want to hear that mineral oil wasn't liquid evil.

A few links about mineral oil...

Top five myths about mineral oil - part 1 and part 2 - at the Beauty Brains.
Mineral oil is non-comedogenic (I can't find the original study - it gives me a 404 error, so here's an interpretation of the article!)
Oils & mineral oil: Cosmeceutical Critique from Entrepeneur magazine with a few good citations.
Link from Cosmetic Dermatology: Practice and Principles regarding mineral oil and cancer.

Join me tomorrow for more fun with maligned products - the ethoxylated ingredients!