The health of human hair plays a crucial role in both male and female appearance, and has a strong psychological and social importance. Beautiful, strong and healthy hair is broadly desired. However, hair is highly exposed to harsh factors such as heat, chemical treatments, pollution and watering that can cause damage on the hair physicochemical properties. There is great interest not only in developing products for the protection and recovery of damaged hair, but also in developing effective protocols to investigate the efficacy of innovative hair care products. Claims for cosmetic products, as well as hair care products, are a strategy to obtain successful marketing and promotion. These claims need to be substantiated by efficacy tests, whether they be in vivo, ex vivo, or in vitro studies.
