Is a fasting insulin level of 4 microunits per milliliter (mU/mL) within the normal range?

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From the Research

An insulin level of 4 is likely low and potentially concerning, though interpretation depends on the units of measurement and testing context. Normal fasting insulin levels typically range from 5-25 μIU/mL (35-175 pmol/L) 1. If your insulin level is 4 μIU/mL, it's at the lower end of normal or slightly below normal range. Low insulin levels can occur in healthy individuals but may also indicate conditions like type 1 diabetes, pancreatic insufficiency, or hypopituitarism. The value should be interpreted alongside blood glucose levels, as the insulin-glucose relationship is more informative than insulin alone. Key factors to consider in the interpretation of insulin levels include:

  • The clinical context, such as symptoms of hyperglycemia or hypoglycemia
  • The presence of risk factors for diabetes or other metabolic disorders
  • The results of other diagnostic tests, such as glucose tolerance tests or HbA1c measurements 2 If you're experiencing symptoms like increased thirst, frequent urination, unexplained weight loss, or fatigue, consult your healthcare provider promptly. They may recommend additional tests such as glucose tolerance tests, HbA1c, or C-peptide levels to properly evaluate your insulin production and glucose metabolism. Insulin levels fluctuate throughout the day based on food intake, stress, and other factors, so a single measurement provides limited information without clinical context. It's also important to note that the relationship between insulin levels and glucose tolerance can vary across different populations and individuals 3. Therefore, a comprehensive evaluation by a healthcare provider is necessary to determine the significance of an insulin level of 4 and to develop an appropriate plan for management and follow-up.

References

Research

Identifying prediabetes using fasting insulin levels.

Endocrine practice : official journal of the American College of Endocrinology and the American Association of Clinical Endocrinologists, 2010

Research

Diabetes Mellitus: Screening and Diagnosis.

American family physician, 2016

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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