I have heard of the sugar issues too. My sister's 2 Chihuahua's have always had that sugar issue. Now, I never had. I keep nutristat on hand but have not needed it. I admit that I love my tiny. I love taking her with me and being that small it is easy to do!! My Ginger that was 4.-4.5 at her heaviest was not bred for a tiny she just ended up being the runt of the litter. She was a nice size to take with me but this time I wanted even smaller. I know I may be bad for that but I am 55, no children, my dogs are my childeren and I want one with me at all times! I travel, I want a little one I can put in my bling bling bags, dress pretty and entertain me!! I need that since we lost our daughter....my dogs are my kids now!! I am lonely, grief-stricken and will do what I need to do to make myself happy.