The best treatment for dry skin may not be a lotion at all. Dry skin is the result of a problem with the stratum corneum and it’s ability to hold water within the tissue. Many times this can be the result of a deficiency in the quantity or types of lipids (fats) that the skin employs to waterproof our bodies. In the past it could be easily said that lotions are mostly water and they would not deliver sufficient quantities of lipid to the skin to improve its waterproofing abilities. These lotions typically felt good when they were initially applied to the skin, but they often had the net effect of drying it out – leaving the skin drier than ever. As the water in the lotion evaporates from the skin surface, it pulls some of the skin’s own water with it. Although lotions tended to be easier to spread over the skin, dermatologists often preferred to recommend products in a cream or ointment base, because these types of emollients would supply more of the moisture trapping lipids.
With advances in the technology of formulations, this paradigm has shifted somewhat. Currently, some lotions can be quite lipid-rich and some creams quite watery. In addition to the lipid content of emollients, another consideration is their pH. The optimal pH for skin care products would be in the acid range. Yet most consumers will have little information to guide them in their choice of emollient, either in terms of its water content or its pH. A recent study by Shi and coworkers examined the pH and water content of a number of emollients available in the US. We have summarized this information in our free booklet, Taking Good Care of Your Skin.