is considered to be a low fasting blood sugar
Normal fasting glucose levels are 70-99 mg/dl. Below that hypoglycemia symptoms will appear, such as you indicated, "I notice when my level is around 60 - 70, I seem to get lightheaded easier." For more info on Hyypoglycemia go here
http://diabetes.niddk.nih.gov/dm/pubs/hypoglycemia/index.htm , or Google "hyperglycemia".
is considered to be a high fasting blood sugar