Actually the basics of the glycemic index thing have been around for a long time. I was given a list of foods I should eat when I was diagnosed with borderline hypogycemia back 21 years ago, and that list more or less matches the GI list.

Also, if you look at low GI items, you'll see that they tend to be complex carbs ... and the whole idea of complex and simple carbs has been around forever ... only I think it was too complex for some people to understand, so they reworded it into "Glycemic Index" and for some reason that was easier to understand ... go figure.

And the GI diet idea doesn't try to deprive you of anything. They don't tell you to avoid protein or fat. Basically all they are trying to tell people is to get away from eating simple sugars, and eat more complex carbs (along with proteins and fats) ... in other words ... getting back to a well balanced diet.

Oh, incidentally ... the diet that diabetics are supposed to eat is a healthy diet which most people should aim to eat because it keeps the blood sugars on an even keel rather than fluctuating all over the place.