The American Diabetes Association guidelines suggest that individuals keep their fasting blood sugars between 80 and 130, and no blood sugar throughout the day greater than 180. This would correlate to a hemoglobin A1c, which is an average three-month blood sugar test, of less than 7 percent. The reason there are guidelines about blood sugar control are because higher blood sugars than that have been shown to promote the progression of complications of diabetes like, numbness, tingling, neuropathies, vision loss or retinopathy, and also kidney disease.