Sunscreen Myths, Dos, and Don’ts

Let’s talk about one of the most important and most misunderstood products in skincare: sunscreen. Between social media misinformation, the appeal of “SPF makeup,” and the belief that sunscreen is only for beach days, a lot of people are leaving their skin unprotected every single day. As a medical spa focused on building and preserving healthy skin, we see the long-term consequences of skipped sun protection more than most. Here’s what you actually need to know.

The Biggest Myth: Your SPF Makeup Is Protecting You

This is probably the most common misconception we hear, and it’s worth addressing head-on. Foundation/makeup or powder that lists SPF on the label is not a substitute for sunscreen because there is no federal regulation on how much SPF must be present in cosmetics that claim sun protection.¹ What’s more, the amount of product you would need to apply to your face to actually achieve the labeled SPF is far more than what any person realistically puts on. Studies show that most people apply only 20–50% of the amount needed for full coverage. So even if your foundation claims SPF 15 or SPF 30, you are almost certainly not getting that level of protection from it. Makeup SPF can offer a small, supplemental layer of defense. But it should never be your primary or only sun protection. Always apply your skincare products first, followed by a dedicated sunscreen, then apply makeup as the last step.

Why Sunscreen Belongs in Your Daily Routine, Year-Round

• UV Rays Don’t Take a Day Off: UV radiation reaches your skin on cloudy days, cold days, and yes, even indoors. Up to 80% of the sun’s UV rays can penetrate cloud cover.² That means a gray Minnesota winter morning still carries real UV exposure and skipping SPF because “it’s overcast” isn’t as safe as it feels.
• Being Inside Isn’t a Free Pass Either: This one surprises people. Standard residential and office windows block virtually all UVB rays but allow between 45–75% of UVA rays to pass right through.³ UVA is the longer wavelength that penetrates deeper into the skin and is primarily responsible for photoaging, collagen breakdown, and pigmentation changes. If you have a window-facing desk, drive during daylight hours, or spend time near windows at home, you are accumulating UVA exposure every single day, even without ever going outside. There is a reason we often see more photoaging and uneven pigmentation on the left side of the face in patients, especially those who drive regularly.
• The Skin Cancer Numbers Are Serious: Skin cancer is the most common cancer in the United States. Research estimates that 1 in 5 Americans will develop skin cancer by the age of 70.⁴ In 2024 alone, over 200,000 new melanoma cases were identified, with nearly 8,300 deaths attributed to the disease.⁴ Daily sunscreen use has been shown to meaningfully reduce that risk. A landmark randomized controlled trial in Australia found that consistent sunscreen use reduced melanoma incidence by 50%.⁵ A separate Norwegian study found that using at least SPF 15 lowered melanoma risk by 30%.⁵ Beyond cancer risk, regular sunscreen use is one of the most evidence-backed strategies for preventing premature skin aging.

What Are Free Radicals, and Why Does It Matter?

UV radiation doesn’t just cause sunburn. It also triggers the formation of free radicals inside the skin. Free radicals are unstable molecules that have lost an electron, making them highly reactive. In their search to “steal” electrons from neighboring molecules, they damage DNA, proteins, and the collagen and elastin that keep skin firm and smooth.⁶ Over time, this oxidative damage accumulates and shows up as fine lines, uneven pigmentation, and loss of skin density, even in people who have never had a visible sunburn.

Here’s the important part: standard sunscreen filters block UV rays, but they don’t completely stop free radical formation inside the skin.⁶ That’s where antioxidants come in. When antioxidants are included in a sunscreen formula, they help neutralize free radicals before they can cause damage, offering a layer of protection that goes beyond SPF alone.⁷ Research has shown that a combination of antioxidants like vitamins C and E, paired with broad-spectrum UV filters, provides meaningfully greater protection against both photoaging and UV-induced skin damage than sunscreen alone.⁷

This is one of the reasons we specifically recommend antioxidant-enriched sunscreens for daily wear, particularly after skin treatments when the barrier is more vulnerable. It’s not a marketing feature. It’s a clinically meaningful upgrade.

SPF: What the Numbers Actually Mean

SPF measures protection against UVB rays specifically, not UVA. The numbers are not linear:⁸

• SPF 15 blocks approximately 93% of UVB rays
• SPF 30 blocks approximately 97%
• SPF 50 blocks approximately 98%

At SPF 30, the difference between that and SPF 100 is roughly 1–2% more blocked rays.⁸ What matters far more than chasing a higher number is finding a broad-spectrum formula (which covers both UVA and UVB), applying it generously, and reapplying every two hours or after sweating and swimming.

No sunscreen is “sunblock.” None blocks 100% of UV radiation.

Sunscreen Dos and Don’ts

• Do apply sunscreen as the last step in your skincare routine and the first step before makeup, every single morning.
• Do choose broad-spectrum SPF 30 or higher for everyday use. This protects against both UVA and UVB rays.
• Do reapply every two hours if you’re spending time outdoors, sweating, or near water. The protective effects of most sunscreens begin to wear off after roughly 90 minutes.
• Do apply to often-forgotten areas: the neck, ears, chest, and the backs of your hands.
• Don’t skip sunscreen on overcast days or because you’re planning to stay indoors.
• Don’t rely on the SPF in your foundation, powder, or cream as your sole protection.
• Don’t assume darker skin tones don’t need sunscreen. While melanin offers some natural protection, it does not prevent UVA damage, photoaging, or skin cancer risk. People with darker skin tones are also more likely to receive a delayed skin cancer diagnosis, making prevention even more critical.⁹
• Don’t buy into the social media narrative that sunscreen causes skin cancer. This claim is not supported by any scientific data. What we do know, unequivocally, is that UV radiation from the sun is a primary driver of skin cancer.¹⁰

Quick Takeaways

• SPF in makeup is not a substitute for sunscreen.
• Wear broad-spectrum SPF 30+ every day, even when it’s cloudy.
• UVA rays penetrate windows and contribute to skin aging.
• Antioxidants provide additional protection against free-radical damage.
• Reapplication matters more than chasing ultra-high SPF numbers.

A Sunscreen We Frequently Recommend

Alastin HydraTint Pro Mineral Broad Spectrum SPF 36

We field a lot of questions about which sunscreen to use, and when a product genuinely earns a recommendation from us, we don’t hesitate to say so. Alastin’s HydraTint has become our go-to for daily wear, and here’s why.

• It’s 100% mineral. HydraTint uses zinc oxide and titanium dioxide as its active ingredients rather than chemical UV filters. For anyone with sensitive skin, rosacea-prone skin, or skin that’s recently undergone a treatment, mineral sunscreen is a much gentler, better-tolerated option. There’s no stinging, no reactivity, and no compromise on protection.
• It actually plays well with other products. One of the most common complaints we hear about sunscreens is that they pill, ball up, or create a white cast that makes layering anything else over them nearly impossible. HydraTint does none of that. It blends seamlessly and holds up under makeup or on its own.
• The tint is genuinely flattering. Rather than a one-shade-fits-no-one formula, HydraTint uses color-correcting pigments that adapt to your natural skin tone, giving you a sheer, healthy glow. Many of our clients wear it alone without any additional foundation. It evens out the complexion, covers minor imperfections, and catches light in a way that looks like skin, not makeup.
• It goes beyond sun protection. HydraTint is formulated with antioxidants that help defend against environmental stressors including pollution, infrared radiation, and blue light from screens, neutralizing free radicals that UV exposure generates in the skin.
• It’s non-comedogenic and post-procedure safe. If you’ve had a laser treatment, a chemical peel, or any procedure that leaves your skin temporarily more vulnerable, this is the sunscreen we recommend. It has been specifically tested to confirm it does not clog pores and is formulated for use on sensitive, post-procedure skin.

If you’re looking for a single product that combines daily sun protection, light complexion coverage, and antioxidant support into one step, this is an excellent option.

Shop HydraTint Pro Mineral Broad Spectrum SPF 36

SPF is not seasonal. It is not optional on cloudy days. It is not covered by your foundation. And it is not something to second-guess based on social media trends. Daily broad-spectrum sunscreen is one of the simplest, most proven investments you can make in your skin’s long-term health and appearance.

If you have questions about sunscreen or want a recommendation based on your skin type and current treatment plan, we’re always happy to help. Your skin protection routine is an extension of the work we do together in the treatment room, and it matters.

Sources

1. Mayo Clinic Health System. “Myth or Fact: SPF in Makeup Provides Sufficient Sun Protection.” mayoclinichealthsystem.org
2. Johns Hopkins Bloomberg School of Public Health. “9 Things to Know About Sun Safety and Skin Cancer.” publichealth.jhu.edu, 2024.
3. University of Wollongong. “Can You Get Sunburnt or UV Skin Damage Through Car or Home Windows?” uow.edu.au, 2025.
4. American Cancer Society. Melanoma Skin Cancer Statistics, 2024.
5. Stanford Medicine Department of Dermatology. “Sunscreen Fact and Fiction: What the Science Says.” med.stanford.edu, 2025.
6. ScienceDaily / University of Bath. “Sunscreen Doesn’t Protect as Well as It Could: Here Is What Is Missing.” sciencedaily.com, 2022.
7. ISDIN Skincare. “Antioxidants in Sunscreen: What and Why?” isdin.com, 2025.
8. Mayo Clinic Health System. “5 Sunscreen Myths.” mayoclinichealthsystem.org, 2023.
9. Medchurn. “Sunscreen in 2025: New Tech, Better Formulas, and Persistent Myths.” medchurn.com, 2025.
10. The Skin Cancer Foundation. “Sunscreen Safety: The Facts.” skincancer.org, 2025.

Author: Julie Davis,Founder & CEO, Renew MedSpa. Julie is passionate about evidence-based aesthetics, skin health, and patient education, helping clients make informed decisions about treatments, skincare, and wellness.

© 2026 Renew MedSpa. All rights reserved. Unauthorized reproduction, distribution, or republication of this content without prior written permission is prohibited. This article is intended for educational purposes only and should not be considered medical advice or a substitute for consultation with a qualified healthcare professional.