Is SPF on sunscreen important?
Do you wonder what ‘SPF’ on sunscreen bottles means? What does SPF measure and why should you care?
SPF sounds short and simple, but the reality is a little more complicated.
What does is protect us from?
Here things get a little less straight forward. SPF is the measure of how well a sunscreen protects the skin from harmful UVB rays, the ones that cause sunburn.
It does not measure the level of a sunscreen’s protection against UVA, the harmful rays that cause aging and wrinkles.
That doesn’t mean that sunscreen doesn’t provide protection against UVA and UVB – because it does. In most countries, alongside SPF on the sunscreen label, are the words “Broad Spectrum”.
What does Broad Spectrum mean?
Broad Spectrum is your assurance that a sunscreen protects your skin from both UVA and UVB.
BUT, no sunscreen can block 100% of UVA and UVB rays.
In terms of percentages, sunscreen with an SPF 15 filters out approximately 93 percent of all incoming UVB rays. SPF 30 keeps out 97 percent and SPF 50 keeps out 98 percent. These may seem like small differences, but if you are light-sensitive, or have a history of skin cancer, those extra percentages will make a difference.
How reliable is the SPF rating?
Finally, a sunscreen’s SPF is only reached if sufficient sunscreen is applied.
Studies show that most people apply only half to a quarter of the suggested amount, meaning the actual SPF on their body is lower than advertised.
Give the SPF a chance
- Use a high SPF sunscreen and apply it generously 15 minutes before sun exposure to allow ingredients to fully bind with the skin.
- Reapplying regularly is just as important as putting it on in the first place, so reapply at least every 2 hours, immediately after swimming, toweling off or heavy sweating.
However you perform, give your skin the best chance of protection.