I am a type 2 diabetic, 75 years old, on insulin. I have been a diabetic for
about 40 years and have used blood glucose meters for the last 15 years. I
used my meter exactly as you suggested, that is to determine which foods caused
the largest increases in my BG readings. I took readings before my meals and at
intervals after the meal to determine the total rise and it's curve (time vs.
rise) By this means I established my own food regimen and was able to get off
medication for about 10 years. My final food regimen ended up very close to
the PALEO diet (and up to a few years ago I did not know what PALEO meant).
It also agrees pretty close with the Glycemic index.