Sweet potatoes, healthy or not??

Being a type 2 diabetic, from a far to full youth, lol, i need to know what the GI rating is of foods that i consume!
You see foods of a high GI rating become blood sugar fast, making them dangerous!! and as any informed person knows, blood sugar controls it all, including cancer!!!

I have been told that the sweet potatoes are healthy, so i checked on them.

Boiled or raw, they are around a rating of 45 and thats good, but!!!! when made into oil cooked like sweet potatoe chips, they become 75 then when baked, they become a rating of 95, oh shit!!!!!
From this i will stick with my low GI charisma sputs and just boiled sweet potatoes.