Role of the fatty acids on hair
When botanical oils such as baobab are applied to the surface of the hair, a variety of different things can occur, depending upon the composition of the fatty acids in the oil. Short and medium chain saturated fatty acids such as lauric, palmitic, and stearic have a linear molecular geometry, which permits them to diffuse through gaps in the cuticle layer and to penetrate into the cortex where they can impart suppleness and elasticity to the hair. Spectroscopic studies have also shown that monounsaturated fatty acids such as oleic acid can likewise penetrate into the interior of the hair strands. This can be beneficial for parched hair that has been damaged by the environment. However, it is important to note that hair that is extremely porous can soak up too much of these oils and become limp, greasy, and even frizzy. Frizz occurs because excess fatty acids can swell the hair and cause the cuticle to lift and the surface of the hair to become rough and unruly.
Higher molecular weight saturated fatty acids and polyunsaturated fatty acids are too large and bulky to easily diffuse through the cuticle into the central portion of the hair. They sit on the surface of the hair and form an occlusive film. This seals water inside the hair and also prevents humidity from getting into the hair. The film also reduces static electricity and provides emollient properties, making combing and detangling much easier.
Baobab oil is interesting in that its fatty acid profile is approximately one-third saturated fats, one-third monounsaturated fats, and one-third polyunsaturated fats. Thus, it works to improve softness and elasticity when the saturated fats and oleic acid penetrate the hair shaft, while the polyunsaturated fatty acids on the surface create a film that acts as an emollient and slip-agent, making detangling easier. Additionally, the film adds gloss and shine to your tresses, while maintaining an optimum moisture balance by minimizing diffusion of moisture into or out of hair.
