Petroleum and mineral oil do not have the capacity to clog your pores. That's a myth.
Mineral oil
Clear, odorless oil derived from petroleum that is widely used in cosmetics because it rarely causes allergic reactions and it cannot become a solid and clog pores. Despite mineral oil’s association with petroleum and the hype that it is bad for skin, keep in mind that petroleum is a natural ingredient derived from the earth and that once it becomes mineral oil USP (cosmetics- and pharmaceutical-grade mineral oil), it has no resemblance to the original petroleum. Cosmetics-grade mineral oil and petrolatum are considered the safest, most nonirritating moisturizing ingredients ever found (Sources: Cosmetics & Toiletries, January 2001, page 79; and Cosmetic Dermatology, September 2000, pages 44–46). Yes, they can keep air off the skin to some extent, but that’s what a good antioxidant is supposed to do; they don’t suffocate skin! Moreover, mineral oil and petrolatum are known to be efficacious in wound healing, and are also among the most effective moisturizing ingredients available (Source: Cosmetics & Toiletries, February 1998, pages 33–40).
Petrolatum
Vaseline is pure petrolatum. For some unknown and unsubstantiated reason, petrolatum has attained a negative image in regard to skin care, despite solid research to the contrary. Topical application of petrolatum can help the skin’s outer layer recover from damage, reduce inflammation, and generally heal the skin (Source: Acta Dermato-Venereologica, November–December 2000, pages 412–415).
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