There's no "official" Type IV diabetes yet, however it is something that's been being researched for about seven years now. Type 4 diabetes is the proposed term for diabetes caused by insulin resistance in older people who aren't overweight or obese (like myself) and is linked to an excess of regulatory T cells. A 2015 study with mice suggested this type of diabetes is real and might be widely under diagnosed because it mimics so many other medical issues but still requires human testing. I would concur that the rest of anonymous' post is pure speculation and opinion.

You can check out the data at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4670283/