THE BEST SUN PROTECTION IS THE ONE YOU APPLY EVERY DAY
Too many skin concerns are the result of damage caused by the sun. Protection is the best form of prevention. It is important to consider both UVB and UVA rays. They do not have the same wavelength, meaning they do not penetrate the skin at the same depth.
UVB
(B for burns) are responsible for sunburn. They only affect the surface of the skin during sun exposure. They represent 5% of UV rays.
UVA
(A for aging) penetrate deeper into the skin. They are responsible for collagen breakdown, pigmentation spots, premature aging… They penetrate through windows, clouds… which is why daily protection is essential even if you are not directly exposed to the sun. They represent 95% of UV rays.
Both UVA and UVB rays reduce your skin’s immune response and increase inflammation.
WHAT IS SPF?
SPF (Sun Protection Factor) is a measure of how effective a sunscreen is at protecting the skin from UVB rays. The SPF numbers found on your sunscreen measure protection against UVB rays only.
SPF does not measure protection against UVA rays. To also be protected against UVA rays, you must ensure your sunscreen provides broad-spectrum protection. This indication ensures protection against UVA rays of at least one-third of the UVB protection. If your packaging includes the mention UVA/UVB, broad spectrum protection, or broad spectrum, it means the sunscreen provides dual protection equivalent to one-third of the UVB protection indicated. Otherwise, UVA protection is not guaranteed.
There is also another protection rating used under Asian regulations: the PA rating. It is expressed with “+” signs from 1 to 4 and measures protection against UVA rays. A PA++++ rating provides strong protection against UVA rays.
PROTECTION LEVELS
If your skin normally burns after 10 minutes of sun exposure, applying an SPF 15 sunscreen would allow you to stay in the sun without burning for about 150 minutes (15 times longer). This is an approximate estimate that depends on skin type (phototype), the intensity of sunlight, and the amount of sunscreen used. SPF is actually a measure of protection against UVB exposure and is not intended to determine how long you should stay in the sun.
SPF protection scales are not linear:
SPF15 blocks 93% of UVB rays
SPF30 blocks 97% of UVB rays
SPF50 blocks 98% of UVB rays
Thus, an SPF 30 sunscreen offers only 4% more protection than SPF 15, and SPF 50 only 1% more than SPF 30. The SPF mainly determines the duration of protected exposure.
THE RIGHT PROTECTION
For optimal protection, experts recommend using a sunscreen with a minimum SPF of 30 and applying about half a teaspoon to the face. Most people do not apply enough sunscreen, often using only a quarter or half of the recommended amount, which reduces its effectiveness. To ensure your sunscreen provides full protection, apply it generously and reapply regularly regardless of the SPF level.