Why would type 2 diabetes be treated with insulin?

High glucose: In the early stages, t2dm can be treated with diet and wt loss. Wt loss is always good, but next step are drugs that target the core defect: Insulin resistance, poor Insulin response to meals with drugs like metformin, actos, januvia (sitagliptin). In time, that may not work either, and then you need to use insulin. Wt loss may work to get you off insulin.