How do Doctors test for Hypoglycemia?
Reading the Results of the Glucose Tolerance Test
Even when good test results are available, many doctors don’t know how to read them. Most of the literature defines Low Blood Sugar as being a measured level below 50 mg/dl or even 40 mg/dl, so if your test doesn’t show any measurements below these, your doctor may conclude that you don’t have hypoglycemia.
The blood sugar level at which symptoms appear varies widely from one person to the next. One person could experience symptoms at 60 mg/dl or even 80 mg/dl while another could show test results of 40 mg/dl without any symptoms at all. In addition, it may be the change in blood sugar level rather than the absolute value that is causing your symptoms.
Dr. Ross, hypoglycemia expert and co-author of Hypoglycemia, The Disease Your Doctor Won't Treat, explains that anything more than normal variations in your GTT results should be interpreted as the effects of hypoglycemia. A graph of blood sugar levels against time that shows a drop below about 50 mg/dl is a standard result for a hypoglycemic. Harder to interpret, perhaps, but still signaling a hypoglycemic reaction, is a graph in which the sugar level drops to around half of the fasting level while remaining above 60 mg/dl. This is called relative hypoglycemia, since it is the low level relative to the fasting level that causes the problem.
Many doctors will discard any test in which the blood sugar level remains above 50 or 60 mg/dl, and tell you that you do not have hypoglycemia.
How can I tell which type is affecting me?
There are two major types of hypoglycemia, reactive and fasting. In reactive hypoglycemia, the symptoms are a reaction to eating, while in fasting hypoglycemia symptoms appear after fasting for 5 or more hours. 80-90% of all hypoglycemics suffer from reactive hypoglycemia.
If you have Reactive Hypoglycemia, you are probably hungry or feeling ill less than 5 hours after you eat. There are many underlying causes, but the symptoms can almost always be controlled by diet. If you experience symptoms of hypoglycemia in the range of 2-5 (some sources say 1½-5) hours after a meal or snack, and eating makes you feel better, it is possible that you have reactive hypoglycemia. (In some severe cases, the sugar reaction occurs almost immediately after eating, but this is a result of the sugar spike rather from low blood sugar.)