Ktani's Hair Sense: Curly Hair and Cosmetic Mineral Oil

Curly hair, and "African-American" hair in particular can be dry. Often, products marketed for the latter contain not only mineral oil but petrolatum and lanolin and sometimes vegetable oils. Petrolatum is greasy, sticky and contains wax ^[1], lanolin is a greasy, sticky wax and both can be difficult to remove from hair. Cosmetic (USP/BP) mineral oil used on its own can be lightweight, enhance curls and moisturize hair. It can be removed easily even with a sulfate-free shampoo or conditioner only, when used in small amounts. It is a non-drying oil, not a liquid wax like jojoba oil. A drying oil can leave “a dry, hard and tough film” on hair and have environmental consequences as well ^{[2, 12, 15]}.

"African-American" hair is often said to be more fragile than other hair types, yet there are no actual differences between it and Caucasian and Asian hair to explain this, except as it has been shown in research, it has less apparent moisture, not less protein. It is believed that the difference in observed fragility is down to hair care practices. One of the hair care practices mentioned, aside from the obvious ones like chemical processing and combing and brushing, or a less obvious one like over twisting hair, is the manipulation of the hair when using styling aids ^[3].

With its emollient, moisturizing, and detangling properties, mineral oil may reduce or eliminate the friction and breakage manipulation can cause when using styling aids, and they may no longer be necessary. Better curl formation can result by using mineral oil alone. Unlike other natural products, oils, or butters, it does not make hair "stiff".

Mineral oil sold as baby oil is usually inexpensive, lightweight and can be fragrance-free. Lightweight fragrance-free USP/BP mineral oils are sold to keep wooden cutting boards from warping. Fragrance-free USP/BP mineral oils are sold as laxatives in different weights.

Mineral oil can rehydrate dry hair, and prevent unneeded trims of previously dry ends for those wanting to grow their hair longer. When a small amount (small drops) are evenly applied to damp to wet hair for hair lacking moisture, it can help keep moisture in the hair as it can in skin by slowing down evaporation "even under extremes of low humidity" [4], and allow good curl retention. It also slows but does not seal out access to the hair by atmospheric moisture ^[6], and help to, or prevent frizz. For hair with a good moisture level, it can be used on dry hair to help maintain that level.

There is no reason why mineral oil should not moisturize even severely damaged hair caused by chemical processing, or heat styling. Damaged hair can be very dry. Mineral oil is used for thermal protection in other applications [17], and USP/BP mineral oil is often added to thermal protection hair care products. It may be sufficient used on its own for thermal protection for hair, depending on the temperatures used for heat styling [18].

Mineral oil is not sticky. Used in small amounts it is not greasy, which can result in hair looking stringy. Mineral oil can reduce or eliminate tangles, and it is antistatic ^[7]. It can work effectively on hair that has been conditioned or unconditioned. It works most effectively when hair does not have a lot of conditioner on it at one time, or residue (build-up), and when it is not combined with other oils. Reapplication between washes is usually not necessary.

Mineral oil is known to moisturize skin more effectively than vegetable oils and silicones ^{[4, 5, 20]}. It is also known in the cosmetic industry for: ease of spreading; shine; and slip thereby reducing friction ^[5].

The best choice of mineral oil is one with the least ingredients because it is the mineral oil itself that is the effective ingredient needed. Other ingredients may cause build-up, or cause hair to look stringy. Baby oil is often sold with just two ingredients, paraffinum liquidum (mineral oil), and fragrance. Sometimes tocopherol actetate (Vitamin E) is listed. It is used as a stabilizer for cosmetic mineral oil and is often not listed.

USP/BP mineral oil is safe ^{[5, 7, 13]}, classified as natural ^[8], can be biodegradable ^[9], does not clog pores ^[13], has a very long shelf life, and is resistant to bacteria ^{[5, 16]}. Unless there is a rare allergy to it, unlike other natural oils, or butters, mineral oil with its lack of both saturated and unsaturated fatty acids, is not known to cause issues, or make skin or scalp issues worse ^{[13, 14, 20]}. It is also used as a lubricant to manage wounds ^[19]. With such a small amount needed for great results, using mineral oil for hair and skin is managing a limited resource very well ^{[10, 11]}. There is no downside to it at all.

References
1. "Petrolatum/Petroleum Jelly"
http://cosmeticsandskin.com/bcb/petrolatum.php

2. “Understanding the Drying Capacity of Oils”

http://ktanihairsense.blogspot.com/2011/12/understanding-drying-capacity-of-oils.html

3. “Hair Breakage in Normal and Weathered Hair: Focus on the Black Patient”