LONDON (AP) — The World Health Organization has issued its first-ever guidance for how much screen time children under 5 should get: not very much, and none at all for those under 1.

The U.N. health agency said Wednesday that kids under 5 should not spend more than one hour watching screens every day — and that less is better.

The guidelines are somewhat similar to advice from the American Academy of Pediatrics. That group recommends children younger than 18 months should avoid screens other than video chats. It says parents of young children under two should choose "high-quality programming"...