Two women with bare skin on a white cream background. There are plenty of viral skincare ingredients floating around the internet right now. PDRN, a.k.a. salmon sperm? Check. Volufiline, a.k.a. filler in a bottle? Check. But of all these sexy, slightly mysterious newcomers, diaper cream has to be the one I was most surprised to spot on my TikTok FYP. Zinc oxide is the true hero behind the diaper cream craze, which has been a lauded for its skin-soothing properties for decades.