I am not diabetic. However, because of intermittent tiredness and dizziness over the past year, and an escalation of those symptoms recently, I decided to begin testing my blood sugar levels to see if perhaps I had low blood sugar hypoglycemia. I tested 7 times a day and after 36 hours of testing my blood sugar is 64-70 upon morning wakening. After 1 cup of coffee(no sugar, 1 tsp creamer, 1 aspartame)on an empty stomaach I felt faint. My blood sugar spiked to 166-168 each time. Therefore, unless I'm missing something, there is definitely a correlation between caffeine and insulin-resistance. I have Grave's Disease and will inform my findings to my Endocrinolgist today. Tomorrow I shall eat first and see what happens. Quite interesting to me.