Is homemade sunscreen safe to use? Here's why it's 'a horrible idea,' according to experts

A woman sprays some sunscreen on a man at Horseneck Beach in Westport, Mass., on Tuesday, June 25, 2024 as temperatures continue to rise across the Northeast. (Peter Pereira/The Standard-Times via AP)

If you could make sunscreen with items found in your kitchen pantry, should you do it?

Posts from social media influencers and bloggers including recipes to make your own sunscreen have been wildly circulated online, but the dermatologists who spoke to CTVNews.ca call it a “horrible idea.”

Sunscreen recipes trending online 

One example of this trend is from TikTok creator Nara Smith, known for her soft-spoken voiceovers documenting made-from-scratch recipes. She recently shared a video of her and her husband’s homemade sunscreen recipe to her more than eight million followers.

“We all burn pretty easily, so we went with something with a little bit more SPF,” Smith says, as her husband scoops out coconut oil into a glass bowl before mixing in beeswax pellets, shea butter, jojoba oil and, later, zinc oxide to the mixture.

There are several other at-home sunscreen recipes online using oils that can be bought from a grocery store, such as avocado, red raspberry seed and carrot seed oils. Some recipes even tout zinc-oxide-free concoctions.

Is homemade sunscreen safe?

While some recipes make it look easy enough to make at home, experts caution against it.

“It’s a horrible idea and an unnecessary practice. At best, it’s wasting materials and, at worst, it’s going to damage somebody’s skin, either from the material itself or from the lack of protection when they then go out in the sun,” Dr. Renée Beach, dermatologist and founder of Toronto's DermAtelier on Avenue, told CTVNews.ca in an interview.

The various oils typically listed in DIY recipes are merely agents that can be found in legitimate sunscreens to make the product smoother, more spreadable or easier to apply to the skin, Beach said, but are not sunscreens themselves.

Dr. Katie Beleznay, a dermatologist practicing in Vancouver, says she has seen misinformation online about the purported level of SPF protection these oils contain.

“Although some natural oils may provide a small degree of UV protection, the SPF is likely quite low and may not protect against both UVA and UVB,” Beleznay said via email. “I have seen some reports of testing for various oils where the SPF is generally five or less. Needless to say they are not reliable for consistent sun protection.”

Dr. Sunil Kalia, associate professor at the Department of Dermatology and Skin Science at the University of British Columbia and member of the Canadian Dermatology Association, adds these oils may actually provide the opposite effect and enhance sunlight penetration into the skin.

“Therefore, it is preferred when trying to block out the sun rays to use sunscreen filters that have a proven SPF level established and demonstrate to either absorb or reflect sunlight,” Kalia said in an emailed statement.

Oil aside, the zinc powder used in at-home recipes could potentially provide some sun protection, Beach noted, but it’s not going to be rigorously vetted or tested like the sunscreens you can pick up off a store shelf.

Why commercial sunscreens are better for you

Unless those making homemade sunscreens have a licence and a degree in cosmetic chemistry, Beach said, it’s unlikely DIYers will create an effective product and have the necessary preservatives to maintain its efficacy for sun protection.

“There’s a reason why (on commercial sunscreens) can have a lot number and expiry number, and that’s because they’ve been vetted. That’s because they’ve been tested, so the lot number says, ‘OK, this is a good lot. This is a good batch, it was made under these specific laboratory conditions—consistent conditions—and expiry is: guess what, the product’s going to degrade at this point, and therefore, the sun protection factor and the lack of organisms or bacteria in it will not occur prior to this expiry date,’” Beach explained.

Commercially made sunscreens also contain chemicals like bisabolol, butyloctyl salicylate and tridecyl salicylate, which boost their performance to protect one’s skin, Beach said. She added they can be somewhat controversial to use, however, as companies advertise higher SPF though it’s “not necessarily on the sole strength of their organic or mineral sunscreen filters.”

“It might even contain iron oxide, which is a form of pigmentation that’s cosmetically acceptable and also affords more protection, particularly against redness or brown tones,” the dermatologist adds.

The anti-sunscreen movement

Some social media influencers claim using sunscreen causes more harm than good, alleging that using it religiously can lead to a vitamin D deficiency or excess chemical absorption, causing cancer – claims dermatologists say are unfounded.

While some studies have shown that certain chemical sunscreen ingredients can be absorbed into the bloodstream, Beleznay says there is no evidence currently that they pose a health risk.

“Health Canada, the FDA and most dermatologists still consider chemical sunscreens safe, with benefits of protecting the skin from UV damage outweighing any potential risks,” Belezenay said. Anyone who is concerned, she added, can opt for a mineral sunscreen instead, which contains filters like titanium or zinc oxide, which reflect UV.

For those concerned about a lack of vitamin D, Beleznay said, adequate levels can be maintained through diet and supplements, if necessary.

Beach said even in the event that sun exposure is the way to go, the amount would be minimal.

“I can’t tell people how to feel, but here’s the alternative: If you have a vitamin D deficiency and you say, ‘I’m going to have sun exposure,’ your sun exposure would be the equivalent of about 10 minutes a few times a week, baring your arms. It’s small, it’s not going and sunbathing,” she said.

Skipping sunscreen in skincare routines can do more harm to skin than good, with possible impacts including thinner skin and more spots and wrinkles, Beach said, which are on the “more fortunate side” of what could happen after prolonged UV exposure.

“On the unfortunate side of things, you’re going to end up with skin cancer that needs to be cut out, leaving a scar behind, which is permanent,” Beach said. “So, in the balance of things, you’re much better off using sunscreen. Is it the most convenient personal care product that ever existed? No (…) but it’s certainly one of the smartest to use.”

Beach noted that a handful of people are intolerant to sunscreen, but they can still protect themselves from UV rays by wearing a hat with a five-centimetre brim, wearing UV-protective clothing, or avoiding outdoor activities during peak sunlight hours.