What Exactly Is Mineral Oil and Why Is It So Controversial?

You might be thinking that minerals are good and so are oils, so combine them together and you'll have something great, right? What it really is will probably surprise you. According to Dr. Karyn Grossman, board-certified dermatologist and creator of Karyng Skincare, mineral oil is a clear, odorless oil that is the byproduct of the distillation of petroleum to form gasoline.

Here's a geology refresher, courtesy of celebrity esthetician Olga Lorencin: Mineral oil is derived from petroleum (fossil fuel) which is made from the residue of plant and animal life (plankton and algae) that have been exposed to very high temperatures in the earth's crust. Once the crude oil is taken out of the ground, it must be purified and refined. This leads us to mineral oil.

Crude oil can be purified into several grades of mineral oil, says Athena Hewett, founder of Monastery. Technical grade mineral oil is the least refined and is used for the lubrication of engines and machinery. Cosmetic grade is more refined and is used in cosmetics and skin care, hence the name. Pharmaceutical grade is the most refined and is used in skin care and baby products. It's very stable and has a long shelf life.

Mineral oil is also sometimes referred to as liquid paraffin, paraffin oil, unscented baby oil, paraffinum liquidum, liquid petroleum/petrolatum and white oil, according to Dr. Craig Kraffert, board-certified dermatologist and president of Amarte Skin Care, and Nancy Leung, Biossance head of new product development.