How low is too low for blood glucose levels when fasting? I am about 64 hours into what was going to be a three and a half day fast that I have been thinking about extending by one day. My blood glucose is moving between 3 and 3.4 (54 and 61.2), but in previous days has dropped lower in the afternoon/evening periods. I have had a little salt but feel a little lightheaded – nothing too extreme. At what point should I be concerned that my glucose level is too low?
My fasting insulin when tested about a fortnight ago was 5.6 (Australian measurement). A DEXA scan taken five days ago shows I have 34.6% body fat.