Blood sugar reference ranges
Pro Research Analysisby 
Searched over 200M research papers
Fasting Blood Sugar Reference Ranges in Healthy Adults
Fasting blood glucose is a key measure for diagnosing and managing diabetes. In healthy adults, typical fasting blood sugar reference ranges can vary by population and region. For example, a study in Kerala, India, found a mean fasting blood glucose of about 81 mg/dL, with the highest mean (84 mg/dL) in the 50-59 age group. Importantly, there was no significant difference between males and females, but age did affect the average values . In Sudan, healthy adults had a mean fasting blood glucose of 74 mg/dL, with a reference range from about 61 to 88 mg/dL, which is lower than many international standards . Another general reference suggests normal fasting blood sugar levels are between 80 and 120 mg/dL .
Blood Sugar Reference Ranges During Oral Glucose Tolerance Test (OGTT)
The OGTT measures blood sugar at different times after consuming glucose. For healthy adults, the 95% upper reference limits for blood glucose at 0.5 hours and 1 hour after glucose intake are 11.58 mmol/L (about 208 mg/dL) and 11.69 mmol/L (about 210 mg/dL), respectively. These values are higher in individuals with impaired fasting glucose or impaired glucose tolerance .
Continuous Glucose Monitoring (CGM) Reference Ranges
Continuous glucose monitoring provides a detailed picture of blood sugar fluctuations. In healthy Chinese adults, the 24-hour mean blood glucose was about 104 mg/dL, with a recommended upper limit of 119 mg/dL. The percentage of time spent above 140 mg/dL should be less than 17%, and time below 70 mg/dL should be less than 12% . Another study in non-diabetic adults found that daily blood glucose typically ranged from about 77 to 144 mg/dL . Measures of glycemic variability, such as standard deviation and mean amplitude of glycemic excursions, also have established normal ranges for adults without diabetes .
Blood Sugar Reference Ranges in Special Populations
Critically Ill Patients
For critically ill patients, maintaining blood glucose within 70–180 mg/dL is associated with better survival, especially in those with lower HbA1c levels. Spending less time in this range is linked to higher mortality .
Infants After Surgery
In non-diabetic infants after cardiac surgery, reference ranges for individual glucose measurements were 85–229 mg/dL on the first postoperative day and 69–149 mg/dL on subsequent days. Mean daily glucose levels ranged from 122–137 mg/dL initially, then 95–110 mg/dL as the infants stabilized .
Animal Models
In laboratory mice (Mus musculus), fasting blood glucose reference ranges were 72–105 mg/dL, with no significant difference between males and females .
Conclusion
Blood sugar reference ranges can vary by age, population, and health status. For healthy adults, fasting blood glucose typically falls between 74 and 120 mg/dL, but local studies may show lower or higher values. OGTT and CGM provide additional reference points for post-meal and continuous monitoring. Special populations, such as critically ill patients and infants after surgery, require tailored reference ranges. Understanding these variations is essential for accurate diagnosis and effective management of blood sugar levels 1234+5 MORE.
Sources and full results
Most relevant research papers on this topic