How to create a truly moisturizing product?
Probably, each portfolio of cosmetics producer or technologist-formulator includes at least one product with moisturizing claim. It seems that there are no more issues in this field. Moisturizing means increasing concentration of water in corneum stratum.
There are two main ways to achieve it: the evaporation of water could be prevented or external water could be carried in. The first approach has a number of instruments (cosmetics components), as well as second does. So, everything is easy, isn’t it? Studies have shown that it is not.
The water flux control is realizing with complex of humectants. The protein keratin and the natural moisturizing factor (known as NMF) are the most important compounds of this system. In addition, the skin contains lipids, forms laminar structures and effectively prevents transepidermal loss of water and electrolytes. However, the problem of these evolutional mechanisms is that these factors are easily washed off the skin, even with simple cleansing routine.
And again, everything seems to be clear – to moisturize the skin, it is necessary to apply products containing lipids and natural moisturizing factors (e.g. include amino acids and their derivatives, small peptides, hyaluronic acid, glycerin, lactate, urea, etc.). However, in practice, everything is more difficult. Studies show that the use of “moisturizing” products, the action of which is based on one or several types of lipids, has virtually no effect on skin moisture; the introduction of individual NMF in cosmetics does not have a prolonged effect; in some cases, the use of ceramides even has negative consequences. At the same time, the comlex application of the three main regulators of skin hydration (ceramides, cholesterol and fatty acids) turned out to be an strikingly effective method of restoring the barrier function of the skin and the ideal level of hydration.
So, we once again receive confirmation that when solving problems of the skin, the major thing is the correct composition of assets. And you can understand it by studying the natural state and mechanisms of regulation of the human body.