It is a vitamin that actually does not fit the standard definition of a traditional vitamin. In fact, it is better classified as a fat – a fat that is absolutely essential to our biological process, but which our bodies do not synthesize. What is this amazing, yet illusive vitamin? It is vitamin F. Perhaps better known as linoleic acid, an omega-6 essential fatty acid (EFA). It plays a crucial role – in tandem with omega-3 EFAs – in brain function, normal growth, skin and hair regeneration, bone health, and metabolic function. In the world of aesthetics, vitamin F is typically found in skin-nourishing formulations as linoleic acid. This powerhouse ingredient comes with a laundry list of benefits, but in skin care it may be best known for its ability to heal, hydrate and plump. What It Is There are two types of essential fatty acids – alpha-linolenic acid (ALA), an omega-3 EFA, and linoleic acid (LA), an omega-6 EFA. These are considered essential, because they cannot be synthesized by the human body. The word "linoleic" is derived from the Greek word "linon," which means flax, and "oleic," which translates to "relating to, or derived from oil." All essential fatty acids are straight-chain hydrocarbons, and linoleic comprises 18 carbons and two double bonds. It is a polyunsaturated fatty acid used in biosynthesis, and it forms the lipid component of the cell membranes in the body. How It Works Essential fatty acids are necessary to normal growth and function of healthy cells. They are vital to the synthesis of tissue lipids, and in the life and death of cardiac cells. These characteristics make EFAs important to healthy skin and hair – it helps maintain shine and strength in hair. In skin care, linoleic acid provides anti-inflammatory, moisturizing and healing support. It also helps fight acne, softens the skin, and keeps it supple and youthful. EFAs can also help facilitate the penetration of other active ingredients such as antioxidants, because of their ability to permeate the skin barrier. Deficiencies are more likely to occur with omega-3 than omega-6 EFAs simply because omega-6 EFAs are more abundant in our food sources. Regardless, a deficiency in EFAs can result in dry hair and skin, hair loss, poor wound healing, and decreased cell regeneration. Where to Find It Vitamin F is found in a variety of food sources. Linoleic (omega-6) is commonly found in a variety of oils such as safflower, grape seed, poppy seed, sunflower and hemp oil ... to name a few. It is also found in almonds, egg yolks and cocoa butter. Alpha-linolenic acid is also found in seed oils, as well as salmon, emu, flax, soybeans, walnuts, chia and hemp seeds. In aesthetics linoleic acid may be commonly found in skin-nourishing and building formulas. Essential fatty acids are ideal for post-care following corrective treatments such as peels, as they provide anti-inflammatory properties, allow for quicker recover, minimize scarring and relieve pain. With linoleic acid's potent healing properties, it should be a treatment room staple. Not only is it useful in accelerating the healing during the post-corrective treatment, it also can help treat burns, cold sores and other minor wounds. Keep in mind that EFAs are also the building blocks of healthy cells, making them a vital part of any healthy aging regimen.Want to read more? Subscribe to one of our monthly plans to continue reading this article.