This was just a fasting glucose test right? Not a glucose challenge test? Has your doctor suggest a challenge test? If he does be very very careful as you're on a low carb diet. Generally to have this test you should not restrict your carb intake for 3-4 days before. I believe this is because drinking that icky drink when your body's got accustomed to reduced carbs will tend to put you into reactive hypoglycemia.

Furthermore the new recommendations from the ADA indicate that anyone with fasting glucose level of 126 should be tested further.

Jay