In brief: Cancer protection
The connection between diabetes and cardiovascular disease is well documented, if imperfectly understood. One explanation is that high blood sugar affects LDL cholesterol in ways that stir up inflammation, so fat-filled atherosclerotic plaques are more likely to burst and block arteries. Three out of four people with diabetes die from a heart attack or stroke. Diabetes is an even stronger predictor of heart attack than high blood pressure and other well-established risk factors.
The evidence for a connection between diabetes and cancer isn't nearly as strong, but there are hints. People with type 2 diabetes tend to have high insulin levels, and some research sug-gests that cells bombarded with insulin are more likely to turn cancerous. And early in 2005, Korean researchers published a study in the Journal of the American Medical Association showing that the risk of getting cancer and dying from the disease was higher for people with diabetes or with a fasting glucose level greater than 125 mg/dL. The association was particularly strong for pancreatic cancer.
But here's the good news: Metformin (Glucophage) might have cancer-fighting properties. Enough to offset the risk from diabetes? That's hard to say.