Sun Protection 101: SPF Decoded & Smart Tips to Shield Your Skin (part 2)
In Part 1, we explored why intentional sun protection is crucial for preserving your skin’s health, especially in Phoenix’s relentless sun. Now, let’s get practical with how to stay sun-smart. This post breaks down what the SPF in sunscreen means, how to use it effectively, and additional tools to protect your skin while enjoying sunny days.
What Do The Numbers Mean?
SPF (Sun Protection Factor) shows how long your skin is protected from UVB rays compared to no sunscreen. For example, SPF 30 offers 30 times longer protection, blocking about 97% of UVB rays.
Rule of thumb
SPF 15: ~93%
SPF 30: ~97%.
SPF 50: ~98%.
SPF 100: ~99%.
NOTE: Beyond SPF 50, extra protection is minimal (<1%), so don’t think that using an SPF 100 is going to protect you the whole day- you’d be surprised how people think this!
Applying SPF Correctly
SPF’s effectiveness drops by 20–50% with sweat, water, or uneven application. Follow these steps:
Amount: Use 1 oz (a shot glass) for the body, or 1/4–1/2 tsp for face/neck. Too little reduces SPF 30 to ~SPF 5.
Timing: Apply 15–20 minutes before sun exposure.
Reapplication: Reapply every 2-3 hours outdoors, or after swimming/sweating.
Note: SPF values do not add up. Example, layering an SPF 30 and an SPF 50 does not create an SPF 80. The final protection level is only as high as the highest SPF in the combination. However, the benefit of reapplication comes from ensuring more even coverage to avoid missing spots, which is crucial since most people don't apply enough sunscreen in the first place.
Choosing a Sunscreen
Here’s how to pick the right one:
SPF 30–50: SPF 30+ (mineral-based, 15–20% zinc oxide) works for daily use; SPF 50 for high-UV settings (e.g., beach, high altitude) or fair skin (Fitzpatrick I–II).
Mineral vs. Chemical: Mineral sunscreens (zinc oxide, titanium dioxide) form a physical shield on the skin to block UV rays, are gentler for sensitive skin, and work instantly. Chemical sunscreens (oxybenzone, avobenzone) absorb UV rays, turn them into heat, and blend into the skin with less visible residue.
Texture: Pick lightweight formulas that suit your skin type and blend well, even on darker tones (Fitzpatrick IV–VI). Always feel free to reach out for recommendations.
SPF in Makeup: is not to be relied on as your sole form of sun protection. You do not apply enough (remember you need about ½ test for face and neck) in order to get full coverage. Yet, having a tinted powder with SPF is a great way to reapply throughout the day.
Extra Sun Protection Tools
Add these:
Check the UV index. Google for your area or use your weather app. Most weather apps will have this information embedded OR use something like a UV Index App
Physical Barriers: SPF 50+ clothing and wide-brim hats block 98–99% of UV, ideal for 10 a.m.–4 p.m.
Oral Supplements: Yes! Sun Powder supports the skin in shielding against UV rays by supercharging your sun protection with a natural fern extract. Sun Powder is to be used to support, NOT as a replacement to sunscreen.
Shade and Timing: Use shade during peak hours; plan activities for early morning or late afternoon. Reflective surfaces (water, sand) still need sunscreen.
As an aesthetician, I see it daily in the treatment room: clients pour hundreds into serums and facials, yet neglect SPF, minimizing their skin’s potential. Knowledge alone won’t save your complexion—action will! Hope this helped give some clarity and inspired some new habits within your daily and skin routine.
