The United Nations on Wednesday released its first-ever recommendations on physical activity for children under five, with disputed advice on subjects ranging from screen time to "tummy time".
The guidelines from the World Health Organization may read to some parents like common-sense practices, including not exposing babies under one-year-old to screens.
But several experts noted that WHO's broad recommendations were based on thin evidence and chastised the agency for adopting overly simplistic definitions of key terms, notably "sedentary screen time."
WHO's "glossary says that it excludes 'active screen-based games where physical activity or movement is required', but that's not very clear in my view."
Andrew Przybylski, director of research at the Oxford Internet Institute at Oxford University, agreed that while restricting screen time among young children appeared to "make sense... in many ways the conclusions drawn about screens are out of step with scientific evidence of harm."