The plasticising effect of moisturisers on human skin in vivo: A measure of moisturising potency?

Background/aims: Moisturisers have many different effects on the skin, but increased plasticity is an important effect of moisturising. We have studied the short-term effects of six commonly used brands of moisturisers on the plasticity of normal and atopic skin. Methods: Measurements of skin mechanics and capacitance were made in 25 healthy volunteers and 15 patients with atopic dermatitis, before and after moisturiser application. Results: Baseline mechanical values did not differ in the two groups. Capacitance was significantly lower in atopics (P < 0.001). All moisturisers increased distensibility and hysteresis of normal as well as atopic skin. Vaseline® and Locobase® caused significantly greater distensibility increases than other moisturisers tested in normal skin, and Vaseline® caused a significantly greater increase in the hysteresis of normal skin. Hysteresis was unaffected by Kerodex® and Clinique® in normal skin. No differences were seen between the effects of different moisturisers in atopic skin. Capacitance measurements fell significantly in normal skin, possibly because of residual cream on the skin surface, while an increase or a significantly smaller reduction were seen in atopic skin. This may reflect better absorption of the moisturisers in atopic skin. Conclusions: The results suggest that high lipid moisturisers cause significantly greater changes in plasticity of normal skin than low-lipid moisturisers, and that atopic skin is influenced to a higher degree by moisturisers than normal skin.