The Role of Lipids in the Process of Hair Ageing

Abstract

An obvious sign of ageing is the loss of hair colour due to a decrease or lack of melanin in hair fibres. An examination of the lipid levels and structure of grey hair determined using µ–FTIR revealed a high correlation between the characteristics of lipids located in the cuticle and the water dynamics of the fibres. Therefore, a deep study based on external and internal lipid extraction, an analysis using thin layer chromatography coupled to an automated flame ionisation detector, calorimetric analyses and the physico-chemical evaluation of the delipidated fibres were performed. Hairs were evaluated to identify changes in the organisation of these lipids using Fourier transform infrared spectroscopy and their effect on the water dynamics of the fibres. The primary differences observed for the lipid extracts from white hair compared to brown hair were the lower amount of the internal lipids extracted, which were primarily composed of free fatty acids (FFAs) and ceramides, with a higher content of lower phase transition peaks, indicating increased unsaturated compounds that promote higher fluidity of the lipid bilayers. The virgin white fibres exhibited lower levels of embedded water, with lower binding energies and higher water diffusion, indicating higher permeability. The IR study confirmed the low lipid levels and the greater disorder of white hair. These results may be of interest for cosmetic treatments to which patients with grey hair may be subjected.

Advancing Lip Augmentation: State-of-the-Art 2D and 3D Analysis for Assessing Volume Enhancement and Lip Line Redefinition

“…More and more young people undergo aesthetic surgical procedures for lip augmentation to obtain the commonly sought-after appearance [31][32][33][34]. In addition, aging creates a spectrum of undesirable changes in the lips, as for the rest of the face [11,12,35]. The upper lip undergoes dermal atrophy and stretches vertically, leading to a thinner and less visible vermilion border [18].…”

Novel surfactants and their application as universal lubricity aids

“…Human hair is primarily composed of up to 95% keratin and 1%-9% lipids (Coderch et al, 2023). The lipids consist of triglycerides, wax esters, free fatty acids, and squalene.…”

“…This method uses electrostatic adsorption. Hair typically has an isoelectric point (ISP) of around 2.5-3.7, which is largely due to the free fatty acid content (Coderch et al, 2023;Parreira, 1980). The ISP can increase significantly to as high as 4.5 by using shampoos containing highly effective surfactants, which is due to these surfactants extracting a significant amount of the free fatty acid from the hair.…”