Derms Sound Off on Why Homemade Sunscreen Is This Summer’s Biggest Don’t

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Neenah, WI dermatologist Victoria Negrete, MD has seen some bad sunburns—including one particularly sad case that came as a result of using coconut oil in place of sunscreen.

The naturally inclined patient’s thinking? That coconut oil offers SPF protection, which Dr. Negrete stresses is NOT the case. 

“It’s not FDA-regulated and it’s completely dependent on the type of coconut oil,” she says. “There is no way to determine the ability to protect the skin. I only recommend sunscreens regulated by the FDA.”

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Like Dr. Negrete, New York dermatologist Sapna Palep, MD has also treated patients who made the very problematic decision to apply DIY sunscreen. “I once had a patient make a sunscreen with titanium oxide, aloe vera and coconut oil!” she says. “She got burnt very badly.”

While the homemade sun-protection route might make some heads scratch, these patients are not alone in their thinking. According to an article published in the Health Communication journal at the start of summer, a search on Pinterest for the terms “homemade sunscreen” and “natural sunscreen” revealed that, out of “189 pins, the majority of pins (95.2 percent) positively portrayed the effectiveness of homemade sunscreens and 68.3 percent recommended recipes for homemade sunscreens that offered insufficient UV radiation protection.”

So why doesn’t it work? As Dr. Palep explains, apart from the whole FDA-regulation thing, in the case of her patient’s titanium oxide–fueled recipe—which is loosely based on an ingredient that’s found in many sunscreens on the market—there’s a lot of science behind it. 

“For starters, zinc oxide and titanium dioxide are reactive ingredients, so it’s not possible to guarantee that the dispersion of these ingredients will be stable over time in a homemade sunscreen,” she says. “And sunscreens are intended to be exposed to sunlight, so ingredients contained in the formula need to be stable—not only while inside your sunscreen’s packaging, but also on the skin.”

Plus, most of us don’t have R&D facilities in our houses, and Dr. Palep points out that sunscreen testing, in particular, requires extensive research and laboratory time. “The effectiveness of your sunscreen formulation must be proved and measured by parameters that will assure you that it is performing as it should.”

“Otherwise, you are just guessing.”

New York dermatologist Shari Marchbein, MD agrees and refers to the DIY-idea as downright dangerous. “They do not meet the standards for protection and safety. You have no idea if what you are making is safe and effective and you will be leaving your skin susceptible to the sun’s damaging rays,” she says. “Dermatologists recommend using a broad spectrum [meaning it protects against UVA and UVB] sunscreen with at least a SPF of 30 that is also water-resistant.”

And, besides the very big threat of getting burned, these recipes have the potential to disrupt your skin in other ways: “Because they are not tested, we don't know how they will behave once on the skin,” New York dermatologist Ritu Saini, MD says. “They can cause irritations and allergic rashes.” 

"Some things you can mix up and use—like a DIY face mask," Germantown, TN dermatologist Purvisha Patel, MD says in summation. "But leave sunscreen to the companies that have tested and made large batches of safe, efficacious product.”