Your co-worker is full of crap! First of all, there is no such thing as "borderline" diabetes. Either you are diabetic or you are not. Levels anywhere above the norm are considered diabetic. When my blood sugar is high, I do get sleepy but I have never fallen asleep during work. One time my blood sugar was over 500 and I worked just fine. Tell her you don't buy it and if she doesn't stop, you will report her.