The Multifunctional Value of Sunscreen-containing Cosmetics: Part 1

Introduction

Sunscreens are perceived as gooey, sticky, uncomfortable products that are difficult to apply and distasteful to wear. This accounts for dismal compliance when dermatologists ask patients to use daily sunscreen. Since the time delay between accumulated sun exposure and skin cancer can be more than 20 years, patients do not receive a short-term benefit from photoprotection. Any marketing genius will tell you that compliance requires both self-perceived short- and long-term benefits in order to reinforce positive behavior. This insight into the human psyche led skin care companies to develop the concept of the "multifunctional cosmetic," which by definition delivers several benefits in one bottle. Currently, popular multifunctional cosmetics include sunscreen-containing moisturizers and facial foundations.

 

Sunscreen-containing Moisturizers

Sunscreen-containing moisturizers have dramatically improved photoprotection compliance. These products can provide moisturization by decreasing transepidermal water loss through creation of an environment that is optimal for barrier repair. Through the use of occlusive agents such as dimethicone, petrolatum, and mineral oil, as well as the use of humectants such as glycerin, propylene glycol, and hyaluronic acid, a therapeutic moisturizer can aid in the restoration of the corneocyte and intercellular lipid organization. In addition, a sunscreencontaining moisturizer can deliver effective ultraviolet B (UVB) and ultraviolet A (UVA) photoprotection, thereby contributing to the prevention of sunburn, photoaging, and skin cancer simultaneously. Through the inclusion of active ingredients such as retinol, niacinamide, and/or green tea, additional antiaging benefits may be achieved. In short, one bottle of sunscreencontaining moisturizer can be designed to moisturize the skin, repair the barrier, stop sunburn, prevent skin cancer, minimize photoaging, and potentially reverse oxidative insults.

Most sunscreen-containing moisturizers are formulated at a sun protection factor (SPF) between 15 to 30. SPF 15 products can be designed with little UVA photoprotection and they may or may not be labeled as broad spectrum. SPF 30 products must contain both UVB and UVA photoprotective ingredients and are therefore preferred. This logic encouraged the American Academy of Dermatology to restate its sun protective recommendations and raise the minimum recommended SPF to 30. For most formulations, SPF 30 is a nice compromise between photoprotection and aesthetics. Once the SPF raises much above 30, the product becomes sticky. Many highly effective sunscreen filters, such as octocrylene, are thick oils and increasing their concentration in the final formulation leads to poor aesthetics.^[1] Yet, for casual limited sun exposure, SPF 30 provides excellent daily photoprotection.^[2]

 

by: Zoe Diana Draelos, MD