With spring in the air and summer around the corner, the focus in skincare is once again firmly on sun protection. The product you choose can make a big difference to your skin, so it’s worth knowing what the various SPFs have to offer before you commit to one. The first step is differentiating between the two basic categories – physical and chemical.
How they do what they do
Both physical and chemical sunscreens are effective at providing sun protection, but they differ in the way they work. Chemical sunscreens absorb UV rays while physical sunscreens deflect or block the sun’s rays. One advantage of physical sunscreens is that they form a barrier on your skin and therefore start working immediately. Chemical sunscreens, on the other hand, must be applied at least 20 minutes before exposure to the sun.
Get the inside story
You can tell whether the product is physical or chemical by looking at the ingredients. Physical sunscreens are comprised of the minerals zinc oxide or titanium oxide, while chemical sunscreens contain chemicals such as octylcrylene, avobenzone, octinoxate, octisalate, oxybenzone, homosalate and helioplex.
Sensitive skins might react more to certain chemical sunscreens, in which case a physical sunscreen might be the better option. Zinc oxide in particular is very effective at soothing skin prone to irritation. Those with a preference towards reducing the chemical load on their skin might also be drawn to physical sunscreens. These sunscreens do, however, have a distinct downside. The mineral actives can leave a white tint on your skin, especially the titanium oxide formulations. On the upside, the more advanced mineral formulations have micronised the mineral particles in these products thereby reducing this tendency.
Take the broad path
An important consideration is the spectrum of protection provided. Not all physical sunscreens are broad spectrum. Titanium oxide for example provides UVB protection but not the full spectrum of UVA. Zinc oxide provides both UVA and UVB protection, however the range of protection depends on the specific active used in the product. Check the label for information and only choose products that provide UVA and UVB coverage.
There is some evidence to suggest that physical sunscreens might be more effective at preventing pigmentation. The sun breaks down the efficacy of chemical sunscreens quite quickly, hence the need to regularly reapply the product to maintain an adequate level of protection. With a physical sunscreen, reapplication is not a constant concern – unless you swim or sweat it will remain on the surface of your skin, protecting you against sun damage. For this reason, you may want to consider switching to a physical sunscreen for your face.
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