It depends on what u eat before that.. like if i eat fries or some sinful stuff the night before n takes long time to breakdown, my sugar will b on the higher side. Otherwise mine were on the 4+ side usually with occassional 3.8/3.9
Some people are just genetically less tolerant to glucose. If your baseline is 5.3 or 5.4 post fasting then that’s probably what your body is capable of.