TikTok is a short video sharing social media platform that has grown rapidly since its launch, amassing over 1 billion monthly global users as of September 2021. ► We argue that public health is served by paying urgent attention to the potential health- related implications of TikTok and suggest research agenda to inform decision- makers, health providers, researchers and the public. ► Specific research priorities include investigating health- harming product promotion, medical advice/illness portrayal, dis/misinformation spread, sensitive or hateful content dissemination, problematic usage or addiction and platform corporate activity.