You do need some sugar/carbs though, it is what your brain runs off of. That,and sometimes you need sugar or carbs when your blood sugar is low. Even if it isn't a life-threatening low, it still affects people negatively.
I become anxious and have panic attacks more often when my sugar is low, or it becomes hard for me to follow conversations. My mom becomes Queen Bitch.(she even acknowledges this,when we suggest she needs to be fed.)And we both will get shaky hands and sometimes a headache, though that's rare.
Having a carb/sugar with protein I find doesn't seem to spike my levels enough to were I'm sleepy, but keeps it pretty even. Though it's hard for me to say because I don't have a meter, because me and my mom, while not diabetic, have blood sugar issues of our own.(She's Hypoglycemic, I have Insulin resistance from PCOS.)