May 20, 2005
Question from Rhode Island, USA:
During recent blood tests, a month apart, my doctor discovered a fasting blood glucose of 156 mg/dl [8.7 mmol/L] and 146 mg/dl [8.1 mmol/L]. My A1c was 6.4 at the second testing. My average overall blood glucose is 115 mg/dl [6.4 mmol/L] with dietary control, but the fasting blood sugar average using self-testing is 150 mg/dl [8.3 mmol/L]. My gallbladder was removed 20 years ago due to gallstones. I'm wondering if there is a relationship between the bile running through my system all night and the higher fasting glucose level. If there is no known relationship, I'm wondering what other explanations there may be for the morning fasting test being the highest rather than the lowest of the day. My doctor and two nutritionists did not have information on this topic.
There is no relationship between gallbladder disease and diabetes. The reason the fasting glucose is elevated in diabetes, despite not having eaten anything over the night, is a fundamental one. The liver makes and stores glucose. It is the job of the liver to keep the body supplied with glucose between meals as the brain uses glucose as its required fuel. When diabetes occurs, there is either insufficient insulin or resistance to insulin at the level of the liver that allows the glucose output to go unchecked. In addition, during the early morning hours, there are hormones secreted by the body that antagonize insulin’s effects on blood sugar. The end result is that blood sugar still rises over night, even though you haven’t eaten anything, when diabetes is present.