SAN FRANCISCO (KRON) -- TikTok, Instagram, YouTube, and Snapchat require users to be at least 13 years old to have an account. But a new nationwide study conducted by University of California San Francisco researchers found that the majority of 11 and 12-year-old children already have accounts, and about six percent have a secret social media account they hide from their parents. The study includes data from a national sample of over 10,000 children between the ages of 11 and 15. It was published in the January issue of the journal Academic Pediatrics. Researchers wrote, "Our findings reveal a high prevalence rate of underage social media use in early adolescence." Jason Nagata, a pediatrician at UCSF Benioff Children’s Hospitals and the lead author of the study, said, "TikTok is the most popular social media platform for children, yet kids reported having more than three different social media accounts, including Instagram and Snapchat."   Before parents cave into their child's peals for iPhones and creating their own accounts, they may consider this: the study found that 1/4 of children reported elements of addiction while using social media. Underage social media use is linked with greater symptoms of depression, eating disorders, and ADHD, according to the study. Supreme Court considers a possible TikTok ban New data shows 25% of children with social media accounts reported often thinking about social media apps, 25% said they use the apps to forget about their problems; 17% tried to use social media less but couldn’t; and 11% said using social media too much had hurt their schoolwork.  (Photo by Jens Kalaene/ picture alliance via Getty Images) The most popular platforms were TikTok (67.1%), YouTube (64.7%), and Instagram (66.0%). A majority (63.8%) of preteens reported social media use. Researchers said 6.3% of children with social media accounts admitted to hiding one from their parents’ knowledge. "Every parent and family should have a family media plan to ensure children and adults stay safe online and develop a healthy relationship with screens and social media," said Nagata, a father of two young children. "Parents can create strong relationships with their children by starting open conversations and modeling good behaviors. This is something I try to do with my own children."