I would suggest she tries the program created by Dr. Neil Barnard in this case as he actually uses a low fat high carb diet in order to reverse diabetes. Both my father and father-in-law got rid of the medications (my inlaw even had to take insulin before the program) and have overall improved their health, lost weight and are feeling much more energetic. My father was able to be out of his medications after two months and my father-in-law in 4 months.
Here's the Amazon link for book about the program and you can also read the reviews of many people who have successfully changed their for the better as well: http://www.amazon.com/Neal-Barnards-Program-Reversing-Diabet...