HOW DOES SUNSCREEN WORK?
Sunscreen contains ingredients which filter out UVA and UVB rays.s. UVA can cause premature skin ageing, whilst UVB can cause burningg and skin cancer.
The Sun Protection Factor (SPF) in sunscreen determines how longng your skin can stay protected from these rays. For example, if it takes s 20 minutes for your skin to burn, using SPF 15 sunscreen should prevent reddening by 15 times longer. The higher the SPF, the longer your skin should stay protected.
You should apply at least a shot glass full of sunscreen in order to achieve the full potential of the SPF. Reapply every one to two hours, and after swimming.
No sunscreen can block all UV rays.