A few years ago the Diabetes Health magazine published an article stating that diabetics should maintain a good BG average and A1c, and avoid a roller coaster type of control. The roller coaster control involves having many highs and lows, and that would involve data widely scattered above and below the average. Blood sugars that rise and fall on the path of a roller coaster are traumatic to the body. Experiencing this trauma over and over again for a long period of time can lead to diabetes related complications, even if the A1c is good. I will demonstrate with two examples.
Patient A has test results 40, 55, 65, 100, 135, 145, and 160. The average is 100, but there are numbers that indicate unhealthy highs and lows.
Patient B has test results 72, 80, 94, 100, 106, 120 and 128. The average is again 100, but the data is more closely packed, and none of the numbers are undesirable.
Patient B is experiencing much better control, and is much less likely to have diabetes complications. The "standard deviation" (SD) is a measure indicating how closely the data is distributed above and below the blood sugar average. Patient A had much larger deviations from the average of 100. Patient B had smaller deviations, so the SD was much better. I try to keep my SD close to 20, but it is difficult to do. My A1c's have been in the 5.4-6.4 range for almost 15 years, but when I have too many highs and lows, my SD is higher and I can feel the neuropathy symptoms in my left foot. I used to have some spots of retinopathy in both eyes because of a roller coaster control..
The purpose of this discussion is to demonstrate the fact that a very good blood sugar average can still involve diabetes complications if there is a significant number of highs and lows over a long period of time. Don't rely solely on a blood sugar average and A1c. Try your best to avoid so many highs and lows. A good average accompanied by a stable control is the best way to avoid complications. Proper dieting and well chosen exercise routines can help very much in avoiding the highs and lows.
I had A1c's no higher than 6.1 for almost 10 years, but had the beginning stages of neuropathy and retinopathy. My control had been tight, but it was necessary to make it even tighter. I stopped having so many highs and lows and after a few months had passed, the retinopathy disappeared. The neuropathy is still present in one foot, but I rarely experience any pain. If I have high blood sugar for several hours there is sometimes mild pain during the night. I have been a diabetic for 69 years, and have not had any serious complications. I want to keep it that way!!