Everyone in North Korea is heartbroken over leader Kim Jong Un’s apparent weight loss, said an unidentified resident of Pyongyang quoted on the country’s tightly controlled state media, after watching recent video footage of Kim.

The rare public comment on Kim's health came after foreign analysts noted in early June that the autocratic leader, who is believed to be 37, appeared to have lost a noticeable amount of weight.

“Seeing the respected general secretary...