TikTok is abundant with “beauty hacks,” but some of them—like freezing sunscreen—are major flops. One as of late involves people squeezing their sunscreen into an ice cube tray to freeze it. The goal is to make the sunscreen nice and cold, so that when it’s applied on a scorching-hot day, it feels good. Here, skin-care experts sound off on why this isn’t a trend to try if you want reliable SPF protection that won’t leave you with a sunburn.
Why Freezing Sunscreen Is a Bad Idea
“Please don’t freeze your sunscreen,” says cosmetic chemist Michelle Wong, aka @labmuffinbeautyscience, on TikTok. “Sunscreens are a blend of oil and water called an emulsion, and just like oil and water, it wants to separate. Everything is held in place by emulsifiers, but this is just a temporary stopping point. If you give it a good enough reason, it will separate. And freezing is an excellent reason. When an emulsion freezes, the water freezes first. All the water molecules hold hands and they actually squeeze the oil droplets together. If the sunscreen separates, then you’re not going to get an even layer on your skin. It’s like painting your skin with a separated paint. You’re going to get patchy coverage.”
Delray Beach, FL dermatologist Dr. Janet Allenby adds, “Freezing products can change the chemical structure and potentially cause them to become ineffective. It would be my recommendation to only use the products as the manufacturer intended for them to be used.”
Don’t Leave Sunscreen in a Hot Car Either
One person commented on Wong’s post, comparing the freezing method to storing sunscreen in a hot car. At a certain point when temperatures are very high, the sunscreen will also separate. According to the FDA, sunscreen products can expire sooner than the date listed on the bottle if they are left in the sun or a hot car because the heat causes the preservatives in them to break down. In these cases, bacteria can grow as well. Wong replied to the commenter, agreeing that heat exposure is bad. “Cold is usually safer than hot, but freezing is really bad.”
Is the refrigerator a good place to store sunscreen? “It should be OK,” says Wong. “There’s some chance of crystallization though, so I’d try cool room temperature first.”
