Childhood cancer survivors who received radiation treatment have nearly twice the risk of developing diabetes as adults, according to a new study.

Children who were treated with total body radiation or abdominal radiation appear to have higher diabetes risks later in life, regardless of whether they exercise regularly or maintain a normal weight.

Researchers at Emory University in Atlanta compared rates of diabetes in more than 8,000 childhood cancer survivors diagnosed between 1970 and 1986, and nearly 3,000 of their siblings who did not have cancer. They found the childhood cancer survivors overall were 1.8 times more likely to have diabetes and the more radiation that was used, the greater the risk. For those treated with total body radiation, the risk was more than seven times greater.

Researchers say doctors must screen for diabetes and pre-diabetes when appropriate and approach survivors with aggressive, risk-reducing strategies. They note more studies are needed to understand how radiation promotes diabetes in cancer survivors.