What are the Pros and Cons of Chemical and Physical Sunscreens?

You may have heard your dermatologist say that the best skin care is sunscreen. And while we all know that sunscreen protects against the harmful effects of UV radiation, namely premature aging and most skin cancers, how should you choose which to use? Should you be concerned about chemicals? Does mineral sunscreen protect as well as chemical sunscreen?  What’s the difference?

Chemical sunscreens are like the undercover agents of sun protection. They contain organic (carbon-based) compounds, such as oxybenzone, avobenzone, octinoxate, and octisalate, which absorb UV rays. Upon absorption, these ingredients convert the rays into heat, which is then released from the skin. This process helps prevent sunburn and other forms of sun damage. 

Pros: People love chemical sunscreens for their lightweight feel and sheer finish, making them a favorite for daily wear under makeup. Some are also water and sweat resistant, thus frequently chosen for active outdoor activities. 

Cons: Some ingredients can irritate sensitive skin, particularly for those with conditions like eczema or rosacea. And discussions about the safety of certain chemical compounds have led to increased scrutiny. While research is ongoing, they remain approved for use by leading health organizations. Some studies also show that they may harm precious coral reefs.

Mineral (or physical) sunscreens contain natural minerals such as zinc oxide or titanium dioxide. Rather than absorbing UV rays, these act as a physical barrier on the skin's surface, reflecting and scattering UV radiation before it can penetrate the skin. 

Pros: Mineral sunscreens are often recommended for those with sensitive or reactive skin due to their minimal ingredients. Many are also deemed “reef safe” as they don’t contain oxybenzone, an active ingredient in chemical sunscreens that certain corals turn into a deadly toxin. 

Mineral sunscreens can also be more durable, providing longer-lasting protection compared to their chemical counterparts. This is attributed to chemical sunscreens' tendency to degrade more rapidly upon UV exposure, though many formulations now include stabilizing agents to extend their efficacy.  

Lastly, physical sunscreens offer immediate protection following application, whereas chemical sunscreens necessitate a waiting period of approximately 20 to 30 minutes to fully activate.

Cons: Physical sunscreens can be thicker and some leave a white cast on the skin, making them particularly unappealing for darker skin tones. Fortunately, advances in formulation have resulted in more cosmetically elegant options, including tinted versions. However, the texture and finish can still be a barrier (pun intended).

Whether choosing a chemical or physical sunscreen, make it part of your daily routine. Dermatologists advise applying a nickel-sized portion for the face and a shot glass-sized amount for the body (more if you have a larger frame) and reapplying every two hours. To maximize your sun safety, wear a hat and UPF clothing. In addition to providing full coverage, UPF clothing replaces sunscreen, thereby reducing how much you need to buy and apply. 

Photo by Antonio Gabola on Unsplash

Sources:

https://www.womenshealthmag.com/beauty/a31940086/physical-vs-chemical-sunscreen/

https://www.centerforsurgicaldermatology.com/should-i-use-a-chemical-or-physical-sunscreen