 Overnight fasting glucose levels are below 70 mg/dL (3.9 mM) in 5% of healthy adults, but up to 5% of children can be below 60 mg/dL (3.3 mM) in the morning fasting state.As the duration of fasting is extended, a higher percentage of infants and children will have mildly low plasma glucose levels, typically without symptoms.The normal range of newborn blood sugars continues to be debated.