Blood glucose normal range
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Understanding the Normal Range of Blood Glucose Levels
Blood Glucose Levels in Different Life Stages
Blood glucose levels, a critical measure of metabolic health, vary across different life stages. In the perinatal period, the fetus receives glucose from the mother, maintaining a lower limit of around 3 mmol/L. After birth, a term neonate's blood glucose can range from 1.4 to 6.2 mmol/L, stabilizing to normal infant, child, and adult values (3.5-5.5 mmol/L) by 72 hours of age .
Normal Fasting Blood Glucose Levels
For adults, normal fasting blood glucose levels are typically defined as less than 100 mg/dL (5.55 mmol/L). However, levels within this range can still predict the risk of developing type 2 diabetes. For instance, fasting plasma glucose levels of 87 mg/dL (4.83 mmol/L) or more are associated with an increased risk of type 2 diabetes, especially when combined with high triglyceride levels or a high body-mass index .
Postprandial Blood Glucose Levels
Postprandial (after meal) blood glucose levels also provide important insights. In non-diabetic individuals, blood glucose levels should be less than 140 mg/dL before meals and less than 180 mg/dL within two hours after eating . These values help in managing and monitoring glucose levels to prevent complications associated with diabetes.
Continuous Glucose Monitoring (CGM) Metrics
Continuous glucose monitoring (CGM) offers a detailed picture of glucose levels throughout the day. In healthy individuals, the 24-hour mean blood glucose (MBG) should be less than 119 mg/dL, with less than 17% of the time spent above 140 mg/dL and less than 12% below 70 mg/dL . These metrics are crucial for understanding glucose variability and maintaining optimal glucose control.
Glycemic Variability
Glycemic variability, the fluctuations in blood glucose levels, is another important factor. Measures of glycemic variability, such as the standard deviation and mean amplitude of glycemic excursions, are higher during the day compared to nighttime. This variability needs to be accounted for in clinical practice and glucose-lowering trials .
Implications of Abnormal Blood Glucose Levels
Abnormal blood glucose levels, whether high (hyperglycemia) or low (hypoglycemia), can lead to significant health issues. Persistent hyperglycemia is a hallmark of diabetes mellitus and can result in complications like kidney problems, heart failure, and high blood pressure. Conversely, hypoglycemia can cause symptoms such as headaches, dizziness, muscle pain, and cognitive impairment .
Conclusion
Maintaining blood glucose within the normal range is essential for overall health and preventing diabetes-related complications. Regular monitoring, a balanced diet, and exercise play pivotal roles in managing blood glucose levels effectively. Understanding the normal ranges and the factors influencing blood glucose can help individuals and healthcare providers make informed decisions about diabetes management and prevention.
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