Did you know that not all UV light is blocked by sunscreen. 

For example, “a sunscreen with an SPF of 15 protects against about 93% of UVB rays and one with an SPF of 30 protects against 97% of rays according to the Mayo Clinic. No SPF actually blocks 100% of UV rays and any sort of UV rays begins [the skin] damage process so it’s important also to to supplement your sunscreen use with trying to avoid direct sunlight.” These are the words of Sam Sheehan of SpotmyUV, we sat down with Sam in episode 8 of the ‘heal thy skin’ podcast and spoke about UV rays, types of sunscreen and a skin mimicking sticker that is raising the awareness of keeping safe in the sun.

In the US they’ve even got some sunscreens that are being advertised as a 100 SPF, which really doesn’t really convey the right message as sun screen just simply can’t protect us from 100% of the UV rays.

There is a common public misconception that the difference between SPF 15 and 30 is double the protection when really it’s just a few percent. 

There are two main types of sunscreen

Those that contain minerals such as zinc oxide, or titanium oxide act as a physical block and are also known as physical sunscreens. They work by reflecting the UV rays similar to how white paint reflects light. Physical sunscreen is affiliated with the white colored noses on beachgoers through the 80s and 90s. Many modern sunscreens contain mineral elements but the manufacturing processes have changed and the manufacturers make the inorganic particles much smaller now so they appear to soak in or not have the same white zinc effect that they used to.

Chemical sunscreens on the other hand don’t actually physically deflect the UV light. Sam explains, “the molecules in chemical sunscreen are there to absorb the UV radiation. Chemical sunscreen absorb the UV radiation that  slowly break down and release heat to prevent damage to the skin which is one of the reasons sunscreen needs to be reapplied”. 

There are a lot of reports in the media of people being badly sunburnt even after reapplying sunscreen. There is an explanation for this, Sam states,

“sunscreen is notorious for [not] being used properly… I say never with almost an amount of certainty that very, very few people actually wear sunscreen properly… there’s a lot of clinical data out there that show average consumers use an average of 25% of what they should actually be”.

What is Spot my UV? 

Spot my UV is a skin mimicking sticker that tells you when your sunscreen is no longer protecting you. The skin mimicking layer is important because sunscreen binds to the sticker in the same way as it binds to your face or your arm or your legs so it’s very accurate across many different activities. 

The mission of Suncayr  is to give you the UV awareness that you need to safely enjoy every day you spend outside. Sunscreen is not a complete solution. Since sunscreen is invisible when it’s both working and not working, how do you know that your sunscreen is still doing its job? 

Listen to the full interview and hear Sam share how his journey into sunsmart awareness bought advanced technology and research to an everyday routine and the importance of knowing you’re protected in the sun.

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Listen to the podcast here: