Moisturization Efficacy: Cream or Lotion?
It is a widely held belief that creams are more moisturizing than lotions, and hence more effective in treating dry skin, for example. While this may have been true when such consumer products first appeared in the market, this is not the case anymore. Today, the difference between creams and lotions is largely related to the types of moisturizers and the consumer sensory expectations. Creams tend to be thicker; however, this can be easily modified by using the right combinations of polymers and emulsifiers. Creams can contain more oils than lotions as in the case of emollient creams, and lotions can contain more humectants, for example, Vaseline™ Intensive Care Deep Moisture Jelly Cream and Vaseline™ Intensive Care Advanced Repair Unscented (See Figure 1 above), respectively. However, this is not always the case. In determining moisturization efficacy, the total level and combination of moisturizers in the product is the most important factor. This is clearly demonstrated in Figure 7, where hydration scores from a 3-week moisturization efficacy study with a 2-week regression phase were compared across different marketed cosmetic therapeutic creams (represented by dashed lines) and lotions (represented by solid lines). There was no direct relationship found between the format and efficacy, in fact, the most efficacious product in the study was a lotion. The entirety of the formulation is responsible for the product efficacy, but this data does suggest that glycerin and total moisturizer levels is a better indicator of performance than product format.If there is no clear relationship between product format and efficacy, how does one select the right product? There are multiple considerations. First, it should be ensured that the product contains the right moisturizer combinations and levels (per INCI understanding as described earlier in this article) to address the patient’s moisturization needs. Second, functional ingredients to address a patient’s secondary skin concerns should be considered and, based on personal experiences, specific ingredients that are not suitable for their skin or have caused issues or reactions in the past such as fragrances, should be avoided. Several key functional ingredients are described in more detail below. Finally, consumers should choose a product that meets their personal sensory preference and price tolerance so they can easily incorporate the product into their daily routine as using a product every day is a key factor to full realization of efficacy.Functional Ingredients
In addition to the core skin lotion and cream ingredients described in the sections above, it is common to include one or more bioactive ingredients that target specific pathways in the stratum corneum and underlying epidermis.Niacinamide (Vitamin B3)
Niacinamide (Figure 8) is the physiologically active form of vitamin B3. This water-soluble vitamin has a variety of dermato