Linoleic Acid

A fatty acid isolated from various plant oils (notably evening primrose, safflower, grape seed, and sunflower oil). It is an occlusive moisturizer and emollient that doesn't leave an oily, sticky residue and is especially suitable for oily and acne-prone skin.
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Origin
Linoleic Acid

Overview

Linoleic acid is a fatty acid, meaning that it is an acid with a long, oil-soluble tail. It is an essential omega-6 polyunsaturated fatty acid, which is a mouthful, so let’s break it down:

- The ‘essential’ just means that our bodies cannot make the acid on their own and that we have to get it from food, supplements, or cosmetics.

- The ‘omega-6 polyunsaturated’ means that the long, oil-soluble tail of the acid contains two double bonds (it is called unsaturated because they are missing some hydrogen atoms). The position of this double bond is calculated from the end of the oil-soluble tail, marked omega, and in linoleic acid, the double bonds start at the carbon atom number 6 counted from the omega end.

Linoleic acid is used in skincare products to help maintain skin structure and to regulate the growth of skin cells. It is necessary for skin barrier function and diseases such as atopic dermatitis or eczema may develop if the skin doesn't contain enough of the acid.

Linoleic acid prevents transepidermal water loss, is moisturizing (occlusive), and is emollient. It is a polyunsaturated fatty acid, meaning that it is especially suitable also for oily and acne-prone skin. It feels light on the skin and doesn't leave an oily, sticky residue.

Vegetable oils are the best source of linoleic acid (notably evening primrose, safflower, grape seed, and sunflower oil). The acid is a clear, colorless liquid that is very sensitive to oxidation and must be protected from air and light.

Linoleic acid has many other benefits aside from its use in skincare. Eating a balanced ratio of omega-6 and omega-3 unsaturated fatty acids in your food might prevent cardiovascular troubles later in life. It has been known for quite some time that sticking to unsaturated fatty acids over saturated fatty acids in your diet will benefit your blood lipid levels.

Science

1
Yang, M., Zhou, M., Jia, Y., He, C., & Song, L. (2020). A review of fatty acids influencing skin condition. Journal of Cosmetic Dermatology.