Mineral sunscreens (also known as physical sunscreens) are notorious for leaving a white cast and not sitting well under makeup, but with new products coming out and old favourites being reformulated, there are far more options out there. Since sunscreen really is the most important skin-care product out there – protecting against UVA and UVB damage, which reduces the risk of skin cancer and also skin ageing – it’s well worth the trial and error to find the perfect one for you. Having said that, we want to take some of that error and guesswork out of your search, which is exactly why we’ve quizzed the dermatologists on all you need to know about mineral sunscreen.
The main difference between mineral and chemical sunscreens is that mineral formulas contain ingredients such as titanium dioxide or zinc oxide, which sit on top of the skin (which is why they’re often thicker and more prone to leaving a white cast) and deflect UV light, thus protecting you from the sun. “Physical sunblocks block the sun’s rays from getting into the skin altogether, like a coat of armour, because the zinc oxide prevents the rays from even entering past the barrier,” said Dennis Gross, MD, board-certified dermatologist and founder of Dr Dennis Gross Skincare.
Chemical sunscreens, on the other hand, contain ingredients such as oxybenzone, avobenzone, octisalate, octocrylene, and octinoxate, which sink into the skin and absorb and detract the sun’s rays. “Chemical sunscreens have ingredients that penetrate into the skin and bond with the sun’s UV rays, transforming them into heat that is then released back out of the skin,” said Orit Markowitz, MD, board-certified dermatologist, and director of Pigmented Lesions and Skin Cancer at Mount Sinai.
The choice of whether you want to use a physical or chemical sunscreen is up to you and depends a lot on your personal preferences and skin type.
“These days, most chemical sunscreens are low irritation”, said London-based consultant dermatologist Dr Mary Sommerlad. However, some people with conditions such as rosacea find the ingredients in chemical sunscreens irritating, making mineral ones a better option. Due to the ingredients necessary in creating a mineral sunscreen and the nature of the product sitting on the skin, people with darker skin tones often find that a white (or even blueish) cast can be left behind. Although formulations these days have been developed to reduce the white cast as much as possible, there are still some products that unfortunately do leave residue.