The Somogyi effect producing high fasting blood sugar is reportedly rare and seen more with type 1 than type 2 diabetes, and the Somogyi effect is not well understood. Insulin resistance together falling insulin levels and stimulation of gluconeogenesis and glycogenesis are likely factors. See https://emedicine.medscape.com/article/125432-overview#a1 If you have a condition that is rare and poorly understood, it might be difficult to find a doctor competent to diagnose it or to admit that they can't. The Hemoglobin A1C test gives an estimate of mean blood glucose level over a period of months by measuring the level of hemoglobin glycosylation. What kind of diet do you follow to control diabetes? I have long followed some variation of the Atkins diet, avoiding sugar and starches that push up one's blood glucose levels, to the extent possible. My A1C hasn't increased from where it was at about 10 years ago. I have also been taking 1500 mg longer acting metformin for nearly 10 years. There are endocrinologists who advise calorie restricted low fat / high carb (semi-starvation) diets and advise against low carb diets, which sounds insane to me. I recently saw an endocrinologist who contends that a calorie is a calorie and that fat makes you fat and that fat should be restricted in my diet. He said that a low carb diet is a very bad idea. It should be kept in mind that very little protein is burned directly. Most is first converted to glucose .