If there’s one skincare question I hear more than any other, it’s about sunscreen (SPF). Some people never leave the house without it, while others only reach for it when heading to the beach or pool. But here’s the truth: whether you love the sun or not, the sun doesn’t always love you back.
As an esthetician with over 20 years of experience, I’ve seen firsthand how confusing sunscreen can be. Clients ask about white cast, sticky textures, breakouts, and whether sunscreen even works. The good news? Sunscreens have come a long way since the days of thick white zinc and overly fragrant coconut lotions. The challenge? Most people still don’t fully understand how sunscreen works, what the SPF number actually means, or why choosing the right formula matters.
Let’s break it down.
What Does SPF Really Mean?
Most people think the SPF number on the bottle tells you how “strong” the sunscreen is. That’s only partly true.
SPF actually measures how long you can stay in the sun before burning, compared to unprotected skin. The average person burns in about 10–20 minutes. Multiply that time by the SPF number, and you’ll get a rough idea of how long the sunscreen will last before you need to reapply.
SPF 15 = about 2.5 hours
SPF 30–50 = up to 4 hours (maximum effectiveness before it starts to break down from sweat, water, or exposure to air)
Here’s what most people don’t realize: all broad-spectrum sunscreens already protect against 93–99% of UV rays. The jump from SPF 15 to SPF 50 is smaller than you think. Instead of chasing the highest number, focus on consistency—reapplying every 2–4 hours.
Chemical Sunscreen vs. Physical Sunscreen
Chemical Sunscreens
How they work: Absorb UV rays, converting them into heat and releasing them from the skin.
Application tip: Must be applied 20–30 minutes before sun exposure.
Pros: Lightweight, no white cast, feels invisible on the skin.
Cons: Not ideal for sensitive skin (rosacea, eczema, melasma). Linked to hormone disruption, allergic reactions, and environmental damage. Some ingredients like oxybenzone are banned in reef-protected areas.
Physical (Mineral) Sunscreens
How they work: Use zinc oxide or titanium dioxide to reflect UV rays like a mirror. Protection starts immediately after application.
Pros: Great for sensitive or acne-prone skin—hypoallergenic, anti-inflammatory, cooling, reef-safe, and non-hormone disrupting. Modern formulations use micronized zinc or tinted options to avoid the old-school white cast.
Cons: Can still feel heavier than chemical sunscreen, though much improved in recent years.
Which Sunscreen Is Best for Your Skin?
If you struggle with rosacea, melasma, pigmentation, or acne, mineral (physical) sunscreen is your best bet. Its naturally anti-inflammatory properties calm the skin while providing immediate broad-spectrum protection.
If you don’t have sensitive skin and want a lightweight feel, a chemical sunscreen might be more comfortable—but be mindful of the environmental and hormonal concerns.
Final Thoughts
Sunscreen isn’t just about preventing a sunburn—it’s your best defense against premature aging, sun damage, and skin cancer. The key is finding a formula you’ll actually wear every day.
For most people, I recommend a physical sunscreen with SPF 30–50. It gives you high-level protection, is safe for sensitive skin, and works immediately. Bonus: many tinted versions now double as a natural makeup alternative.
The bottom line? Sunscreen is self-care. Choose one you love, apply it daily, and reapply often. Your future skin will thank you.