New York - The United Nations on Friday joined some 800 monuments and landmark sites around the world in commemorating World Diabetes Day by lighting its building in blue.

Other sites include the Pyramids and Sphinx in Egypt, the statue of Christ the Redeemer in Brazil, Niagara Falls, the Tower of London, the Sears Tower in Chicago and the Alamo in Texas.

Floodlights were to be turned on at night on the 40-floor UN headquarters in New York to bring the disease to light as an estimated 250 million people now have diabetes type-1 and type-2, 80 per cent of them in low and middle-income countries.

The World Health Organization said the number of people with diabetes could double by 2030.

The current focus in the campaign against the disease is children and teenagers.

"We must do more to inform children and adults about the warning signs of the disease, particularly in the developing world," UN Secretary General Ban Ki-moon said in a message to mark the day.

"Many children in the developing world die from diabetes because they do not have insulin," he said.

The UN said more than 800 buildings and landmark sites around the world were to light up in blue, symbolically to call attention on the impact of the disease on society and to seek improved healthcare. (dpa)