An eight-month-old Colombian baby has been put on a strict diet by doctors, after reaching more than three times the weight of a normal-sized child of his age.

Santiago, who weighs 21 kilograms (46 lb), will be taken off formula milk and fed vegetables and juices to get his weight down to a healthy 8 kilograms (18 lb).

Doctors say there is no medical reason for his weight gain - he has simply been overfed. He now weighs the same as an average five-year-old.