Physical and Chemical Sunscreen; what's the difference?

There's no doubt that sunscreen is one of the most important elements in anyone's daily regime. As an esthetician, I am always taking extra caution as to what I apply to my skin and how it will make my skin look when I'm older. Sunscreen is an absolute essential to prevent premature aging and potential cancers. Before you go and stock up on sunscreen for the rest of the season take into consideration the two types of sunscreen and how they can benefit you.

 

Sunscreens fall into two different types of categories; physical and chemical. Chemical sunscreens work by absorbing ultraviolet radiation (UVR) to minimize its impact on the skin, while physical sunscreens work by reflecting UVR away from the skin. Here's a little more about each:

 

Chemical:

• 
  Chemical sunscreens work by absorbing the sun's rays although some chemical filters can scatter sun rays, but still mostly just absorb them. They contain ingredients such as avobenzone, oxybenzone, and helioplex that act as filters to absorb UVR. They are usually colorless, odorless and more on the runny side than physical sunscreens.

• Chemical sunscreen is best suited for ladies (and males) with a minimal skin routine. They tend to be more irritating on the skin and can cause a reaction if you have sensitive skin. Can also be doubled as a makeup primer depending on the formulation.

 

Physical:  

• Physical sunscreens protect your skin from the sun by deflecting or blocking the sun's rays. They contain ingredients such as titanium dioxide and zinc oxide. Titanium dioxide protects against UVB rays, but not the full spectrum of UVA rays. Zinc oxide protects against the entire spectrum of UVB and UVA rays. They also tend to be thick and opaque and tend to be harder to apply. They also leave a white cast or tint on the skin.

• Physical sunscreens are best suited for all skin types, although if you tend to break out when using mineral makeup, avoid physical sunscreens with titanium dioxide as the main ingredient. This type tends to rub off easily, so make sure you apply it more frequently than you would a chemical sunscreen.

 

Another misconception about sunscreen is, the higher the SPF the better. This is not entirely true. It is recommend to use at least an SPF 50 whenever you're in the sun, or an SPF 40 on the face daily. Sunscreens with really high SPFs, such as SPF 75 or SPF 100, do not offer significantly greater protection than SPF 30 and mislead people into thinking they have more protection than they actually do. Additionally, in order to have broad spectrum protection, the UVA protection should be at least 1/3 of the UVB protection. High SPF sunscreens usually offer far greater UVB than UVA protection, thus offering a false sense of full protection.

 

To read more about SPF in sunscreens, check out FDA's page.