The sun, while essential, is a double-edged sword. UV radiation can accelerate aging, impair vision, and trigger the most diagnosed cancer in the US: skin cancer. Knowing the value of sunscreen is one thing, but understanding SPF values, PA+ ratings, and chemical versus physical formulations is another ball game. Dive into this comprehensive guide to find the perfect sun protection tailored for you.
What are UV Rays?
Sunscreen is more than a beach day accessory—it's a shield against the unseen dangers of UV radiation. UV rays, or ultraviolet rays, are a form of electromagnetic radiation emitted by the sun and some artificial sources like tanning beds. Here's a quick UV primer:
- UVA, with its long wavelengths, penetrates deep into the skin, damaging cellular DNA and accelerating the aging process.
- UVB primarily affects the skin's surface, leading to tanning, redness, and even sunburns.
- UVC, thankfully, doesn't pose a threat as the earth's ozone layer filters it out before it reaches us.
It's essential to recognize that both UVA and UVB can contribute to skin cancer. Hence, opting for a broad-spectrum sunscreen is crucial.
What is PA+?
"PA" represents a sunscreen's UVA defense level. Based on the Persistent Pigment Darkening (PPD) criteria, rankings include PA+, PA++, and PA+++. Here's a quick breakdown:
- PA+ offers 2 to 4 hours of UVA protection.
- PA++ extends protection from 4 to 8 hours.
- PA+++ ensures over 8 hours of protection.
What is SPF?
SPF is measured by two factors – time and efficacy. Generally speaking, the levels of SPF show how much UVB rays will be absorbed by the sunscreen and how long it will take to burn your skin.
Time: An average person starts burning after 10 minutes under direct sunlight. By applying the SPF 15 product, we can provide 15 times the protection of no sunscreen. That means you have 2,5 hours (10 min x SPF-15 = 150 minutes) before your skin turns red.
Efficacy: The higher the SPF, the more UV rays it filters, and you can stay in the sun longer without risk of sunburn. For example, SPF 15 absorbs 93 to 95% of UVB rays; SPF 30 absorbs 97% of UVB rays; SPF 50 absorbs 98%.
In 2019, the FDA stated that the SPF level increased from 50+ to 60+ to provide the best protection. They also require that all sunscreens with an SPF of 15 or higher must have broad-spectrum protection.
What SPF Should I Use?
Consider these three factors when selecting the appropriate SPF: your skin tone, the current season, and your skincare regimen.
SPF and Skin Complexion
- Extremely fair skin always burns quickly, getting a minimal tan or no tanning at all. Use sunscreen with SPF 30 or SPF 50.
- Fair skin burns moderately but tans eventually. Use sunscreen with SPF 15 or SPF 30.
- Medium and olive skin burns minimally and always tans well. Use sunscreen with SPF 15 or SPF 6.
- Dark and very dark skin rarely or never burns and tans easily. Use sunscreen with SPF 6 or SPF 2.
SPF and Season
Cold winter days are not usually filled with sunlight, but you still can get the harmful effects from UV rays. For those who have a pale to light complexion, the experts recommend wearing at least SPF 15 from October through April. People with medium, dark, and very dark skin should use SPF 2 or SPF 6. From May to April, when the sun gives off its strongest light, you should use sunscreen with SPF based on your complexion (see classification above).
SPF and Skin Care Routine
Retinol, vitamin C, benzoyl peroxide, and chemical exfoliants can make your skin more sensitive to UV light. That means you may get sunburned more easily. If you use one of these powerful ingredients, it would be highly recommended to wear sunscreen with an SPF of no less than 30+.
Physical vs Chemical Sunscreen
Each option has its own positive and negative properties. By knowing the difference, you will feel more confident in your product choice.
Physical Sunscreen
- It lasts up to 40 minutes in water
- It takes effect as soon as you apply it
- It contains titanium dioxide and zinc oxide
- It creates a barrier on the skin surface, protecting it from UVA and UVB rays
- It is safe and can be used by people with sensitive skin, pregnant, and kids
- It has a thick consistency, so it is hard to spread on the skin
Chemical Sunscreen
- It lasts up to 80 minutes in water
- It takes effect 15-20 minutes after you apply it
- It contains avobenzone, octinoxate and oxybenzone
- It absorbs UV rays and transforms them into a small amount of heat.
- It can irritate extremely sensitive skin because it includes many ingredients to protect against UVA and UVB rays
- It has a thin consistency and easily spreads on the skin like a lotion
Wrap It Up
Want the best sunscreen? Find one labeled "broad-spectrum" and PA+++. Match the SPF to your skin and season. If you like natural products, pick those with zinc or titanium. And remember, limiting sun time is the safest bet. Before you go, I'd suggest checking out the article titled "Can You Tan With Sunscreen?" for further insights.