Diabetics & cancer

Diabetics are 3 times more likely to develop colorectal cancer than people with normal blood sugar.

Scientists at the University of Cambridge have reported that diabetics are three times more likely to develop colorectal cancer than people with normal blood sugar levels.

The researchers found a continuous relationship between glycated hemoglobin (HbA1c) concentrations and colorectal cancer risk, even in individuals not known to have diabetes.

"When both glycated hemoglobin levels and diabetes status were included as variables in the same model, glycated hemoglobin remained a significant predictor of colorectal cancer risk, while the effect of diabetes was not significant," said Kay-Tee Khaw, principal investigator for the study.

Khaw noted further that glycated HbA1c could predict colorectal cancer independently of diabetes and such other risk factors as obesity and cigarette smoking and do so at concentrations below those commonly accepted as the standard for a diagnosis of diabetes.

For every one percent increase in glycated hemoglobin there was a corresponding 33 percent increase in risk across the population.

The results are based on data derived from the European Investigation into Cancer-Norfolk Study, a prospective population study of the connection between diet and cancer.

"Our work augments the increasing evidence of a link between abnormal glucose metabolism and increased colorectal cancer risk. Earlier research posited a relationship between insulin resistance, glucose and colon cancer, on the basis of the fact that insulin promotes the growth of colon cells and colon tumors. Both diabetes and colorectal cancer may share common predisposing factors. For example, a high-fiber diet and regular exercise may protect against both diseases," said Khaw.