This Is Why You Should Never Leave Your Sunscreen in the Sun

woman taking sun&earth zinc sunscreen out of bag


You might have heard us say “leave your tinted zinc cream on your car’s dashboard to soften it”. However, we want to point out that this advice should only be followed on cold mornings before you head out for a surf. Just like a jar of coconut oil that hardens and softens according to the temperature, your tinted zinc is extremely malleable - aka, not a good idea to leave it in the sun indefinitely. And here’s why. 

Sunscreen breaks down when it is exposed to light and heat.

Do you know why dermatologists recommend reapplying sunscreen regularly? Well, a sunscreen SPF rating stands for the length of exposure your skin can endure without being burned. An SPF30 means that you can stay 30X longer under the sun than when you expose yourself without protection. 

When the clock runs out, it is simply because your sunscreen broke down from extended exposure to light and heat. 

Sunscreen will break down both on your skin and in its container if you leave it exposed for too long. Keeping your sunscreen under the sun means that its composition will melt and degrade, ultimately making it less effective. The Australian Therapeutic Goods Administration TGA assert that any sunscreen on the market must be labelled with an expiration date or “use-by” term, to prevent sunscreen from being too degraded by long heat exposure - aka your tin warming up in your beach bag all summer.

We advise you to use your tinted zinc cream within 24 months of purchase maximum. However, if the zinc cream has been exposed to the point of melting, it is best to discard it for a new one.


How your skin deal with sunscreen melt

Depending on the type of sunscreen you use, your skin deals with sunscreen melting very differently. There are two types of sunscreens: Chemical blockers and Physical blockers. 

Chemical blocker sunscreen is commonly absorbed by the skin to create an inner barrier to UV rays. Unfortunately, it has proven to trigger the creation of free radicals, damage hormonal balance and accelerate skin ageing. Physical blockers (like our tinted zinc cream) instead sit on the skin, creating a veil-like barrier that reflects UV rays so that nothing is absorbed in the epidermis.

When using sunscreen that has been melted by the sun, the chemical blockers might do a lot more damage to your skin - thanks to the now unbalanced chemicals. A physical blocker? Well, it will depend on its composition. Our tinted zinc cream is 100% natural and using it melted means it would quickly be washed away by the first splash of water, and provide little protection. 


All in all, make sure to shade your sunscreen to lengthen its longevity. Using a physical blocker and re-applying regularly is a good idea too. Our tinted zinc cream is 100%natural, SPF30, and perfect for any skin. Shop now.

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