Is melatonin safe for kids? Here's what the experts say

(CNN)Melatonin is a popular over-the-counter sleeping aid, touted as a natural way for adults to fall asleep and used by millions around the world. So why wouldn't it be good for children, too?

"There is a view that if it's natural, then it can't hurt," said Rebecca Robbins, an associate scientist at Brigham and Women's Hospital in Boston, who studies sleep.
"The truth is, we just really don't know the implications of melatonin in the longer term, for adults or kids," she said.
    "People think melatonin is an herb or supplement, but it's a hormone," said Dr. Cora Collette Breuner, a professor in the department of pediatrics at Seattle Children's Hospital at the University of Washington.
      "Does taking it delay puberty? Does it delay the onset of a menstrual period or make it happen sooner? Does it affect somebody that has hormonally mediated disease like thyroid disease? Does it affect something else that is hormonally related, like insulin and diabetes? The verdict is still out on that," Breuner said.