This seems like a great topic for some beauty myth-busting!
First of all, what the hell is mineral oil?
Mineral oil is any alkane between 15 and 40 carbons that didn't come from a plant or animal-based source. That means it's just some nice, simple carbons, with hydrogen atoms attached by single bonds. Typically, mineral oils are produced from a petroleum distillate. The term was originally coined in the 18th century to refer to crude oil byproducts. (By the way: add some fragarance and BAM, you get baby oil.)
There are three big reasons that people cite for their opposition to mineral oil:
1. It comes from petroleum! Petroleum is scary!
2. YOU'RE GOING TO GET CANCER.
3. It will clog your pores and you will be a pizza face forever.
I am going to address these arguments separately.
The "petroleum is scary" argument: Puh-leeze. This is prima facie anti-science. If you don't understand chemistry, you can make lots of things sound frightening based on their component parts. But those of us who took high school science classes know that sodium may explode and chlorine may poison us, but sodium chloride just gives us delicious french fries. Both petroleum and mineral oil may contain hydrocarbons, but you need to address the actual product in question.
The "you're going to die a long and terrible death of cancer" argument: The problem here comes from a lack of distinction between unrefined and refined mineral oil. The World Health Organization classifies untreated mineral oils as Group 1 carcinogens, meaning that they are definitely carcinogenic to humans. The thing is, no one is trying to get you to put unrefined mineral oil on your face. Refined mineral oil, meaning that clear mineral oil you might buy at the drugstore, is classified as Group 3, meaning that there is no reason to suspect that it is carcinogenic.
The "look at your ugly acne" argument: This argument stems from the 1970s when dermatologists were, as a profession, concerned with a condition they termed "acne cosmetica", or acne that is aggravated by cosmetic use. (Now, with modern cosmetic chemists on the job, this diagnosis is all-but-nonexistent!) However, when the American Academy of Dermatology (AAD) convened to look at the evidence against mineral oil... it turned out there wasn't any. As of now, there is no evidence that mineral oil is prone to skin-ruining. As Joseph DiNardo notes, "Based on the animal and human data reported, along with the AAD recommendation, it would appear reasonable to conclude that mineral oil is noncomedogenic in humans."
|I have enough zits already, thanks.|
We've established that mineral oil wasn't sent from the devil himself to ruin your good looks and health. Why might mineral oil be a good thing in makeup or skincare?
Since mineral oils are big, long chains of carbon, they are way too large to penetrate your face. Instead, they sit on top and block water loss, making them an effective occlusive moisturizer. It is also effective at staying on the skin, even if you exercise or dump your head in barrels of water or whatever it is that the kids are doing these days. Rawlings and Lombard add, "Mineral oil is an efficacious skin moisturizer providing occlusivity and emolliency. Its occlusive effects lead to increases in stratum corneum water content by reducing transepidermal water loss. Through this mechanism, mineral oil is used to treat dry skin conditions in both leave-on and wash-off applications. It has been shown to improve skin softness better than wax esters, triglycerides and fatty acids. Its effect is largely confined to the epidermal layers, and as a result of its limited penetration, it is considered to be a very safe ingredient for cosmetic use."
The scientific literature is very clear clear: if you want to try mineral oil, go for it! Slather that shit on!