High blood sugar is among the top four causes of death worldwide, says a study from the Harvard School of Public Health in Massachusetts.

While high blood sugar is one indicator of diabetes, the researchers said a higher-than-normal level can kill before people develop diabetes, WebMD.com said. Researchers at the school's Boston campus said they found health risks increased once blood sugars were higher than normal.

Goodarz Danaei, report author, and his colleagues reviewed information from 52 nations, WebMD.com said. They found that high blood sugar was associated with about 3.16 million deaths each year.

Danaei said results showed that one in five deaths from heart disease and one in eight deaths from stroke were attributable to high blood sugar levels.

At 3.16 million deaths, high blood sugar was behind smoking, with 4.8 million deaths annually, and high cholesterol, with 3.9 million deaths, but ahead of overweight/obesity, at 2.4 million deaths, WebMD.com said.

Copyright 2006 by United Press International