Sunscreen is essentially any product that can be applied topically, either reflecting or absorbing ultraviolet radiation from the sun. Products can range from pastes and gels to sprays and foams that can be applied to the skin and are further subdivided into physical and chemical barrier types. Physical barriers are typically mineral-based, utilizing zinc oxide and titanium oxide, which literally create a physical barrier that mostly deflects UV light. Chemical sunscreens on the other hand, such as oxybenzone or octinoxate, act like filters that absorb UV light from the sun. 

Diligent use of sunscreen is typically recommended to slow or temporarily prevent damage to the collagen-rich connective tissue underlying the skin from degrading, causing wrinkles, sun spots, and saggy skin. More importantly, the American Cancer Society has long recommended the use of sunscreens to prevent the development of multiple forms of skin cancer. Yet, in order for sunscreens to be able to prevent the development of UV radiation-induced skin cancer, they must be considered to behave as a broad-spectrum sunscreen, meaning that they block both UV type A light and UV type B light. 

Most basic sunscreens primarily block UVB light, still allowing the more harmful UVA rays to get through the sunscreen and thus damaging the DNA of the skin’s cells, increasing the risk of cancer development. This of course only happens with prolonged and repeated exposures without much attention to repairing the damage that has already been caused by the previous exposures. 

Unfortunately, some of the chemical ingredients that were previously used to provide much of this broad-spectrum protection were discovered, after decades of use in large scale manufacturing, to cause damage to the skin’s cells and their DNA. This further increased the risk of developing skin cancer even if the sun's rays are being blocked by the sunscreen, due to the toxicity of ingredients. 

As a science, environmental consciousness, and our general relationship to the earth has developed it has become apparent that creating chemically burdened and nano-tech formulations of sunscreens is ultimately harming those who use it and the immediate environment that the individual used the sunscreen in. Today you’ll find that most sunscreens will be water or oil-based, typically with non-nano zinc oxide and a number of other ingredients that can be comprehended by the average person. These can most commonly be slaves, pastes, creams, lotions, and sprays that provide safe and effective protection from the sun and are often combined with botanical extracts to provide added benefits for skin health and cellular integrity. 

So whatever your choice of product may be, as long as it protects the skin from the sun’s harmful rays, it can be considered a sunscreen!

- Dr. Thomas Macsay