I'm a type 2 diabetic, controlled with several different kinds of medications. Which was another drive to quick smoking, its certainly not helping with all the other health issues diabetics can have.
I've only been vaping for a week, and I believe all my juice has been PG based, from 11-18 mg. I just finished an extensive vaping session on the new VP1 with some 24mg juice in it. I've not eaten for a few hours, but I just tested at 125 which is actually pretty good for me.
I haven't noticed any oddities in my daily testings since I've been vaping. Its been steady as usual, only going up or down after I eat, as is normal.
Hope you friend is okay, and that she too can keep vaping instead of falling back on analogs.