Understanding Sun Protection Factor
SPFstands for Sun Protection Factor.
This article explains what SPF numbers mean.
It discusses how SPF is measured and how to determine the right level of protection for your skin.
Verywell / Ellen Lindner
It also offers advice for other ways to protect your skin from UV damage.
A higher SPF value increases your protection, but it’s not a straightforward mathematical equation.
SPF measures the quantity of UV radiation, not exposure time.
This is because the intensity of solar energy varies throughout the day.
In addition, an individual’s threshold for UV exposure varies from person to person.
Pale skin absorbs more UV light than dark skin and, therefore, burns more easily.
The more melanin in the skin, the darker the skin toneand better protection from the sun.
However, ultraviolet A (UVA) rays also pose risks.
They age the skin and contribute to skin cancer.
SPF alone does not protect against UVA rays.
to get the best sun protection possible, look for a sunscreen that provides bothUVA and UVBprotection.
Does Higher SPF Matter?
Yes, higher SPF does matter, but it is unclear where the threshold lies.
A sunscreen with a higher SPF rating blocks a greater percentage of UV light.
However, as SPF ratings increase, the added benefits shrink.
For example:
Sunscreens with higher SPF ratings are typically more expensive than those that offer less protection.
SPF 30 is generally considered the breakpoint, where higher SPF provides only marginally better protection.
Depending on your skin, this may not be meaningful enough to justify its cost.
Is it Better to Use SPF 30, 50, or 100?
When used properly, SPF 30 should provide adequate sun protection for most people.
However, few people use sunscreen correctly.
Under typical-use conditions, research shows SPF 100 provides significantly more protection against sunburn than SPF 50.
But the clothing you wear is also important.
Regular Clothing
Generally speaking, long sleeves and pants are more protective than tank tops and shorts.
UPF clothing is made with fabric that protects the skin from the sun.
UPF clothing is becoming increasingly more common, especially in kids' clothing and beachwear items like rash guards.
Be picky about which jot down of sun-safe clothing you buy.
Protect Your Skin Year Round
Sun protection is not for summer only.
Sunscreen should also be worn in the winter, spring, and fall.
You should also wear sunscreen indoors and while driving because the sun can penetrate through windows.
In your car, transparent window film screens can block out the sun’s rays.
At home, draw the blinds closed during peak sunlight hours.
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