With an average cost of $168 per regimen, pricey products are also taking a hit on adults' wallets.
CHICAGO -- There is a new warning about the skincare obsession among preteen girls on social media.
New research finds that girls as young as 7 are sharing their skincare routines, sometimes using products some researchers say they really shouldn't be.
There is an investigation finding tween skincare routines may be causing more harm, to skin and parents' bank accounts, than good.
Researchers from Northwestern University created TikTok accounts pretending to be 13-year-olds and reviewing 100 skincare videos on TikTok from girls as young as 7.
Among the top 25 most-viewed videos, investigators found an average of 11 active ingredients that could irritate adolescent skin, including citric acid, salicylic acid and glycolic acid.
But the study, which relied on a small sample of 100 TikTok videos, only analyzed ingredients in the 25 most-viewed products, and doesn't provide a complete picture of what all users see on the app.
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Dermatologist and tween skincare expert Dr. Brooke Jeffy says most products made for adults aren't beneficial and can damage sensitive tween skin.
"Many of these skincare products deal with adult skin issues. So, age-related changes, like wrinkles, hyperpigmentation and dullness to the skin, which kids don't have. So, when they use these products, it can really be harmful to their skin barrier," Jeffy said.
Only a quarter of the reviewed videos mentioned sunscreen, though the American Academy of Dermatology and the American Academy of Pediatrics recommend its use for all children over 6 months old.
And with an average cost of $168 per regimen, pricey products are also taking a hit on adults' wallets.