I hear people on this site throwing the term 'Glycemic Index' a lot and I'd like to familiarize myself with how the GI of specific foods affect my diet.
For instance, I have recently started eating potato bread instead of white bread and I'd like a way to compare the Glycemic Index of the two to see how the change will affect my current diet.
Is there a particular source that's good for looking up the GI of specific foods (like Wolfram Alpha is for researching nutritional facts)?