There has been interest in looking at the native foods pre-European diet of the Pima Indians and its ability to control diabetes. You might be interested in this article about it: http://www.spmesquite.com/articles/ancientfoods.html

Of course, they point out how wonderfully low-fat high-fiber these foods are, but what really stands out to me is how these foods are very low on the glycemic index. They mention names of a number of researchers, and some of these people might even be helpful in finding the best way to introduce the concept of LC to the people on the res.

I personally am interested in trying some of that mesquite flour myself!