The homemade sunscreen: Is DIY sun protection safe?

Editor’s note (July 2026): I’ve corrected three things in this post since it was published in 2024. The original version assigned coconut oil an SPF of 4 to 8, suggested that natural ingredients boost a sunscreen’s protection, and advised avoiding chemical UV filters.

Better evidence has since made all three untenable, and I’ve rewritten them below rather than quietly deleting them.

The full reasoning — including what changed my mind — is in Is sunscreen safe? What the evidence actually says. The post’s central argument, that homemade sunscreen can’t be relied on, stands unchanged.

If you’ve spent any time on TikTok or Instagram lately, you’ve probably stumbled onto the latest trend: homemade sunscreen. Coconut oil concoctions whisked in a glass bowl. Beeswax blends cooked up in a double boiler. These recipes are spreading faster than a summer tan.

I love a good DIY project. This is not one of them.

Experts at the American Academy of Dermatology have warned that most homemade sunscreens lack the ingredients needed to shield skin from UV rays — leaving users exposed to sunburn, premature aging and a raised risk of skin cancer.

Research has since confirmed that the popular recipes circulating online don’t deliver a fraction of the protection they promise.

So before you reach for the pantry, here’s why this is one trend worth sitting out.

Why homemade sunscreen is riskier than it looks

Whipping up your own sunscreen sounds appealing and wholesome. In practice, it fails in six specific ways — and each one matters.

It skips testing and regulation

Sunscreens are classified as over-the-counter drugs, which means they undergo strict testing and approval processes. Before hitting the market, all sunscreen products must meet the FDA’s (Food and Drug Administration) rigorous guidelines for SPF (Sun Protection Factor), water resistance, and safety profile.

A kitchen recipe bypasses every one of those steps.

The ingredients aren’t standardized either, so protection varies from batch to batch — and from the top of the jar to the bottom.

This is why, according to the American Academy of Dermatology, most homemade versions do not provide adequate protection. They leave users vulnerable to sunburn and increased risks of skin cancer.

You can’t measure the SPF

Sun Protection Factor (SPF) measures how well a sunscreen protects against UVB rays. Commercial sunscreens undergo rigorous testing to ensure their SPF claims are accurate and effective. There is no home version of that test.

You’ll see recipes credit individual ingredients with an SPF of their own. Coconut oil is often assigned somewhere between 4 and 8.

Those numbers come from spectrophotometer tests run in a dish, not on skin, and they badly overstate what the oil actually does. Tested properly on human skin, coconut oil measures around SPF 1.2.

Not 8. Not 4. Barely one.

And even if the figure were generous, you couldn’t add it to anything. SPF belongs to a tested finished formula, not to a sum of its parts. You cannot stir three ingredients together and total up their supposed protection.

Consumer Reports makes the same point about margin of error: a small miscalculation translates into significantly less protection than you think you have.

Formulation is more precise than it looks

Sunscreens are carefully formulated and tested in registered labs, where precise measurements of active ingredients like zinc powder and chemical filters are ensured.

Particle size alone is a science. In mineral sunscreens, the size of the zinc oxide or titanium dioxide particles determines the outcome — too large and you get a chalky white cast, too small and coverage suffers.

In 2025, University of Sydney researchers did what none of the recipe videos do: they tested one.

They took a wellness blogger’s homemade formula — zinc oxide with coconut, almond, shea, beeswax and seed oils — applied it to human skin samples alongside a commercial SPF 50+, and measured the UV damage underneath.

The commercial product did its job.

The homemade version did not come close.

It won’t stay stable

Lab-formulated sunscreens undergo stability testing to confirm they don’t degrade in heat, light or humidity before the expiration date.

Homemade versions have no such guarantee. They can break down quickly and quietly — plus, who wants to carry around a melting jar of cocoa butter or almond oil on a hot day?

It won’t apply evenly

Even coverage is half the battle. Commercial sunscreens are engineered to spread and absorb quickly so that every exposed inch gets the same protection.

DIY mixtures are frequently thick, greasy or lumpy. They drag rather than glide, sit on the surface instead of settling in, and leave patchy gaps you can’t see.

A buttery concoction in a pretty mason jar photographs beautifully. It doesn’t protect your skin.

It can grow bacteria

Store-bought sunscreens contain preservatives to prevent the growth of bacteria, mold, and yeast. A DIY sunscreen typically lacks these preservatives, increasing the risk of contamination, which can lead to skin infections and other health issues.

A homemade jar usually has none. That raises the risk of contamination, skin infections and worse — and without the sterile conditions of a manufacturing facility, spoilage can start during preparation, before the lid ever goes on.

Is homemade sunscreen safer because it is “chemical-free”?

This is where language becomes misleading.

Everything is made of chemicals.

Water is a chemical.

Zinc oxide is a chemical.

Coconut oil is made of chemicals.

Your skin is made of chemicals.

The word “chemical” does not tell us whether something is safe or unsafe.

A better question is: Has this product been tested, and does it work as intended?

A natural ingredient can be ineffective.

A synthetic ingredient can be safe.

The evidence matters more than the label.

What I would use instead

If you enjoy natural skincare, there is no reason to abandon it.

I still love beautiful oils, nourishing balms, and barrier-supporting ingredients.

Use them where they work best: For moisturizing dry skin, supporting the skin barrier, comforting sensitive skin, and soothing rough patches.

Just do not ask them to do the job of sunscreen.

For daily sun protection, choose a tested, broad-spectrum SPF 30 or higher that you will actually apply generously and reapply when needed.

Look for a formula you enjoy wearing.

Because the best sunscreen is not the one with the most impressive ingredient story.

It is the one you will use consistently.

My updated view

Years ago, I believed coconut oil might offer a small amount of natural sun protection.

I would not write that sentence today.

The evidence has become clearer.

Coconut oil can be a lovely skincare ingredient.

Tallow can be a lovely moisturizer.

Zinc oxide is an excellent sunscreen ingredient.

But none of these facts mean a homemade mixture can replace a tested sunscreen.

Science changes. Good journalism should change with it.

The goal is not to defend “chemical” sunscreen.

The goal is much simpler:

Use protection that has been tested to protect your skin.

Ever tried your hand at a homemade sunscreen? Would you want to go down that route?