Easing sensitive scalp while preserving its microbiota
Sensitive scalp is a scalp condition that is frequently the source of concern and complaints. Extreme scalp scratching and itching, associated with scalp greasiness (due to excess sebum production) and desquamations (dandruff), are characteristics of a sensitive scalp episode and may strongly impact quality of life. In addition, the alteration of hair and scalp appearance can lead to a loss of self-esteem. Unfortunately, when people try to solve a sensitive scalp issue with shampoo or lotions they often cause an imbalance in the scalp’s microbiota, a major factor in scalp health. In response, thanks to plant stem cell technology we have developed a cosmetic active ingredient obtained from the Malus domestica apple and assessed its performance in a shampoo. This paper presents the clinical efficacy tests for our new active ingredient, as well as an in vitro assay, demonstrating its property to ease sensitive scalp while preserving precious scalp microbiota.
The scalp is very special skin with particular features including a higher follicular density than skin on other parts of the body (1).
The scalp has also an abundant nerve network making it more responsive to irritation and itching sensations (2, 3).
It has numerous eccrine sweat glands and sebaceous glands: sweat can act as an irritant, accounting for the frequent itching associated with areas of sweat collection (3).
Thanks to sebaceous glands, the scalp produces a large amount of sebum (4), which is important for the maintenance of epidermal barrier integrity (1), carrying antioxidants to the skin surface (5), the survival of skin microbiota, and for skin protection against solar irradiation (1, 6). However, its alteration may lead to the occurrence of a sensitive scalp (7, 8).
In addition, the scalp is rich in microorganisms composed of both bacterial and fungal communities (9). Whereas the mycobiome is mostly composed of Malassezia species, bacterial microbiota is more diverse with the most abundant bacteria ...