Consider the glycemic index of major sources of carbs. Some complex carbs (WHEAT products!) are worse than table sugar for spiking blood glucose.

The numbers below are often averages from several studies. I wrote them down from a website. Sorry I forgot the address, but it was easy to find with Google.

Barley (pot barley)- 25
Rye bread - 48
Rice, brown=white!!! - 55
Sweet potato - 57
Soda pop - 63
Oatmeal, cooked - 65
Table sugar - 65
Wheat bread, brown=white!!! - 71
Gatorade - 83
Baked potato - 85
Glucose - 100 (by definition)

I try to eat high on this list. Oatmeal is about the cutoff for me.