I don't think you should do the 100 gram at home. I think he should have that
done professionally, if it were to be done. The fasting insulin shows alot, and if elevated can indicate a beginning insulinoma, or insulin resistance.

You just needed to see if he were dipping severely at home.
It is possible he is insulin resistant and has been for a long time, and is
now controlled well with diet. You just don't want to see blood glucose
readings as low as 38 showing up as a surprise. Basically the higher the glucose load, the higher the swing from high to low can be. It is not likely Alan is eating 100 grams of glucose in his meals. So it is not likely he will hit those rock bottom numbers...that we hope. That he didn't hit low lows with the 50 gram load is better..since 50 gr of carbohydrate are conceivable in the diet.
Drinking a 16oz Coke would do it.

What we see here is the typical medical issue of whether doctors ignore something or not.
In your case ignoring the increases of uric acid most likely coming from your
HCTZ drug. And in Alan's case ignoring a strange low # in a test. It is these types of things that bring people to the net..for answers.

You are a real trooper to do the test at home.