I have a couple of relatives with T1D and that was exactly the first thing they were told to do. However doctors know that many people will not do this, and goo

I have a couple of relatives with T1D and that was exactly the first thing they were told to do. However doctors know that many people will not do this, and good doctors are more interested in helping the patient be healthy than being moralistic jerks, and so they prescribe insulin to meet the patients existing needs instead of saying "well you should have eaten better and then you wouldn't be dying so young".