The 5 Most-Asked Sunscreen Questions

We rounded up the top 5 sunscreen questions people ask Alexa, Siri, and Google—and answered them with clarity, science, and zero marketing fluff.

TL;DR

Zinc oxide is the safest active sunscreen ingredient for babies, sensitive skin, and marine ecosystems.
Tinted zinc oxide formulas minimize white cast without using harmful nanoparticles.
You should wear zinc sunscreen under makeup—it often acts as a natural primer.
SPF 30 is plenty for everyday use if applied generously and reapplied often.
"Reef-safe" only means something if the sunscreen contains non-nano zinc oxide and no chemical UV filters.

1. "What's the best sunscreen for sensitive skin?"

Short answer: Look for one with non-nano zinc oxide as the only active ingredient—without chemical filters, preservatives, or synthetic fragrances.

Long answer: Sensitive skin isn't just a marketing niche. It's a daily battle for millions of people (and their kids) dealing with eczema, perioral dermatitis, allergic reactions, or post-sun inflammation.

Most conventional sunscreens use chemical filters like oxybenzone, octinoxate, avobenzone, or homosalate. These filters work by absorbing UV rays and converting them to heat. That sounds okay—until you realize these same ingredients are known skin irritants and hormone disruptors.

A 2020 study published in JAMA showed common chemical filters are absorbed into the bloodstream—even after a single use.

Zinc oxide is different. It doesn't absorb. It sits on your skin and reflects UV rays. It's been FDA-approved for decades. And when it's non-nano (meaning particles are too large to enter your bloodstream), it's even safer.

For sensitive skin, here's your checklist:

✅ Non-nano zinc oxide only (not combined with titanium dioxide or chemical filters)
✅ No parabens, phthalates, petroleum derivatives, or phenoxyethanol
✅ Fragrance-free (even "natural" fragrance oils can cause flare-ups)
✅ Bonus: food-grade ingredients you could pronounce or eat

Product: Waxhead Baby Sunscreen was initially created for our son's eczema. It contains 6 food-grade ingredients, 25% non-nano zinc oxide, and zero junk.

2. "Does zinc oxide sunscreen leave a white cast?"

Short answer: Yes … and no. It depends on the formula.

Long answer: Mineral sunscreen's infamous white cast gave it its reputation as "lifeguard nose paint." But not all zinc oxide sunscreens leave a ghostly residue, and you no longer have to choose between safety and appearance.

Let's break it down:

Raw zinc oxide is white, so the more it is in a formula (and the less dilution with oils and emollients), the more opaque the coverage is.
Tinted formulas use iron oxides to offset the white effect and blend better with most skin tones.
Micronized zinc oxide reduces the visible white cast without using nanoparticles.

The challenge? Most clear or invisible zinc oxide sunscreens use:

✖️ Silicones (dimethicone, cyclopentasiloxane) to fake glide
✖️ Low-zinc formulas (under 10%) that don't offer real protection
✖️ Nano zinc, which absorbs into the body and harms marine life

So yes, you can find zinc oxide sunscreens that don't leave you looking like a mime. But read labels carefully because many "natural" brands quietly sneak in synthetics to make their formulas prettier.

Best compromise: Choose a tinted, non-nano zinc oxide sunscreen with 20–25% zinc. It gives a subtle glow, balances skin tone, and avoids the Halloween effect.

Try this: Waxhead Mineral Tinted Sunscreen for Face. It is 25% non-nano zinc tinted with iron oxides for a warm, semi-matte finish. There is no ghosting.

3. "Can I wear sunscreen under makeup?"

Short answer: Yes, especially if it's a zinc-based sunscreen with a non-greasy finish.

Long answer: Layering sunscreen and makeup used to be a pain. Sunscreen pilled. Foundation slipped. You felt like a glazed donut by 10 a.m.

But modern mineral sunscreens—when formulated correctly—double as a clean primer.

Here's what to look for:

✅ Matte or satin finish: Avoid greasy or overly emollient formulas.
✅ Fast absorption: Sunscreens that dry down quickly create a better base for makeup.
✅ No silicones or dimethicone: These can feel slick and trap sweat and bacteria under makeup.
✅ Tinted zinc oxide: Helps replace or reduce your need for foundation.

Pro Tip: Let sunscreen sit for 5–10 minutes before applying makeup. This lets the formula set and prevents pilling.

Bonus benefit: Zinc oxide protects against visible light, which can contribute to hyperpigmentation. This is especially important if you wear makeup and spend time under indoor lighting or in front of screens.

Double-duty solution: Our Tinted Face Stick acts like BB cream, evens out tone, and layers well under makeup—or replaces it entirely.

4. "What SPF do I need for daily use?"

Short answer: SPF 30 is enough for most people, most of the time.

Long answer: SPF isn't everything. An SPF 50 sunscreen with poor UVA coverage won't protect you, and a broad-spectrum SPF 30 formula with high zinc content won't protect you.

Let's unpack this:

SPF 30 blocks ~97% of UVB
SPF 50 blocks ~98%
That's a difference of just 1%

But here's the kicker: Most people don't apply enough sunscreen or reapply often.

That's why: A well-formulated SPF 30 zinc sunscreen, appropriately used, is usually more effective than a greasy SPF 70 chemical one you avoid using.

You need daily SPF if you:

Drive a lot (UV penetrates glass)
Spend time outdoors, even briefly
Sit near windows or screens
Want to slow visible skin aging

Even cloudy days? Yes. Up to 80% of UV rays penetrate cloud cover.

Bottom line: SPF 30, broad-spectrum, high zinc percentage, should be applied every 2 hours.

5. "Is zinc oxide sunscreen reef-safe?"

Short answer: Yes, when it's non-nano zinc oxide and doesn't include chemical UV filters or synthetic preservatives.

Long answer: Reef-safe isn't just a feel-good label—it's an ecological necessity. Coral reefs are threatened by climate change, overfishing, and, yes—chemical sunscreens.

In 2018, Hawaii banned the sale of sunscreens containing oxybenzone and octinoxate due to their role in coral bleaching. Other locations followed, including parts of Mexico and the U.S. Virgin Islands.

But here's the problem: "Reef-safe" isn't regulated. Brands use it to describe products containing all kinds of sketchy ingredients.

Here's what actually matters:

✅ Only non-nano zinc oxide (and sometimes titanium dioxide) is considered safe for marine life
✅ Avoid petrolatum, octocrylene, avobenzone, octisalate, and synthetic preservatives like phenoxyethanol
✅ Water-resistant formulas matter—so less product washes off into the ocean

What about nanoparticles? Nano zinc oxide may offer more transparency on the skin, but it's been shown to be toxic to marine organisms and can enter coral cells.

So, if you're snorkeling, surfing, or just swimming in the Gulf, protect the reef and your skin by using non-nano zinc oxide only.

Do the right thing: All Waxhead Sunscreens contain only non-nano zinc oxide and food-grade ingredients and are packaged in plastic-free or recyclable packaging whenever possible.

Sunscreen Shouldn't Be a Chemistry Exam

Most people don't have time to decode ingredient labels or memorize SPF charts. That's why they ask:

"What sunscreen can I use on my baby?"
"Is there a zinc sunscreen that doesn't leave a white cast?"
"What's safe to wear every day?"

The answers should be simple, safe, and science-backed—not hidden in fine print.

The best sunscreen is the one you'll use daily, consistently, without hesitation.

And when that sunscreen is made with only zinc oxide and food-grade ingredients, you don't have to worry about skin irritation, hormone disruption, or bleaching coral reefs.

Conclusion: Sunscreen Clarity in a World of Confusion

In a category flooded with marketing fluff, overhyped filters, and "clean" claims that crumble under scrutiny, it's no wonder people turn to voice search with real, human questions. What's safe? What actually works? What won't wreck my skin—or the reef?

The answers, while nuanced, aren't complicated.

To protect your skin, you don't need 15 active ingredients, invisible nanoparticles, or lab-made molecules. You need a proven physical barrier—non-nano zinc oxide—and a shorter list of ingredients.

Let's recap the essentials from the top searched sunscreen questions:

Sensitive skin? Stick with zinc oxide. It protects without penetrating or inflaming.
White cast? Use a tinted mineral sunscreen. Iron oxides blend, zinc protects.
Makeup layering? Zinc is makeup-friendly. Look for fast-absorbing, silicone-free finishes.
SPF confusion? SPF 30 is more than enough when reapplied and paired with high zinc content.
Reef safety? Non-nano zinc oxide is the gold standard. Everything else is either unproven or already banned in Hawaii.

At Waxhead, we make sunscreen without shortcuts. There is no "reef-safe" marketing bait with hidden synthetics, no chemical filters wrapped in natural-sounding language, just food-grade ingredients, high zinc content, and a refusal to compromise.

Why It Matters

Sunscreen isn't just skincare. It's health care. Daily protection against UV damage isn't a trend—it's a non-negotiable if you want to:

Slow premature aging
Avoid cumulative sun damage
Prevent skin cancer
Protect delicate skin (yours and your kids')
Safeguard coral reefs, fish nurseries, and marine ecosystems

That's a lot riding on one tube of cream. But when the sunscreen is simple, effective, and backed by real science, it's one less thing to stress about.

Your Next Step

So, if you're still digging through reviews, trying to decode acronyms, or wondering if that clear spray SPF is too good to be true … here's our answer:

Start with zinc. Start with safety. Start with formulas so clean you could technically eat them.