Photo from Spectrum Healthcare

Madison McGuire

While it is important to wear broad spectrum sunscreen everyday, many people don’t realize that the category of sunscreen should be considered as well. Physical sunscreens, or “sun blocks,” create a barrier on the skin that filters out UV rays, while chemical sunscreens absorb and scatter the sun’s harsh UV rays.

Physical sunscreens contain mineral-based ingredients, such as zinc oxide and titanium dioxide, and work by staying on top of the skin to deflect UV rays away from the skin. These products offer protection from both UVA rays and UVB rays, are safe for babies, are less likely to irritate sensitive skin, and have a longer shelf life. However, more frequent application is required as the thick formula can rub or sweat off. They also take more effort to rub in.

Chemical, or organic, sunscreens contain chemical compounds that absorb UV rays, such as oxybenzone, octinoxate, and avobenzone. Many ingredients are required to create both UVA and UVB protection at higher SPFs. As the organic chemicals absorb UV radiation, their bonds break, and the resulting energy is released as heat. These products are thinner and spread like a lotion, making it more practical for daily use. However, chemical sunscreens increase the risk of skin irritation and increase redness on rosacea-prone skin from the influx of heat on the skin. They only become effective approximately 20 minutes after application and also have an increased risk for clogged pores and breakouts.

In addition, recent research has shown that several active ingredients in these sunscreens enter the bloodstream at levels that far exceed the FDA’s recommended threshold. However, the effects of this systemic absorption on human health is not known and needs further study.

Despite popular debate, there is no optimal category of sunscreen.  Each individual can consider the pros and cons when choosing a product. While chemical sunscreens are preferred by those who sweat a lot and need a water-resistant formulation, physical sunscreens are recommended for those with sensitive skin. Whatever kind of sunscreen you choose, the most important factor is to apply it regularly to prevent future skin damage.

https://www.drdoppelt.com/physical-vs-chemical-sunscreen/

https://www.piedmont.org/living-better/the-difference-between-physical-and-chemical-sunscreen

https://www.drdesjarlais.com/protecting-your-skin/chemical-vs-physical-mineral-sunscreens-pros-and-cons/

https://www.usatoday.com/story/news/health/2019/05/06/sunscreen-chemicals-absorb-your-bloodstream-fda-study/1123513001/