Nation Some sleep-aid gummies contain over 300% more melatonin than labeled, study finds April 25, 2023April 26, 2023 Nada Hassanein, USA TODAY Comments Off on Some sleep-aid gummies contain over 300% more melatonin than labeled, study finds A study finds melatonin gummies, which are not regulated by the FDA, are often mislabeled, putting children at risk.