Can You Be Healthy and Still Have Abnormal Blood Tests?

Reviewed by Dr. Darshit Patel, MD, General Medicine

Routine blood test are often seen as essential tools in modern healthcare. But what happens when your results show abnormal blood tests even though you feel perfectly fine? It’s a common concern: “Why do I have abnormal blood test results if I feel healthy?”

First, it's important to understand how normal ranges in blood reports are defined. Reference ranges are based on averages taken from large populations. Typically, they include 95% of healthy individuals, which means that 5%, even if completely healthy, will naturally fall outside the expected values.

That’s why many healthy individuals may get flagged with unusual lab reports. These deviations are often harmless. Conditions like benign ethnic neutropenia—a common cause of low white blood cells—occur in healthy people from certain ethnic backgrounds (e.g., people of African or Middle Eastern descent) without increasing health risks.

Moreover, lab test interpretation requires context. Factors like:

• Dehydration may raise hemoglobin or kidney markers.

• Exercise or muscle stress can affect liver enzymes.

• Sleep loss and stress may influence glucose and cortisol.

• Menstrual changes can impact iron and hormone levels.

These blood test fluctuations are normal and do not necessarily indicate illness. Yet, they can cause anxiety. A 2019 BMJ Open study reported that over 40% of abnormal results in healthy individuals led to unnecessary tests, a phenomenon linked to false positives in blood tests. ^[4]

So, what causes abnormal blood work in healthy individuals? Most often, it's a mix of personal baselines, timing, and external factors. If you're wondering, “Should I worry about abnormal blood tests with no symptoms?” the answer is usually no—unless results are persistently or significantly abnormal.

Understanding blood tests when you're not sick means seeing them as part of a bigger picture. Lab values should be interpreted alongside medical history, any symptoms, and clinical judgment.

Conclusion:
Yes, you can be healthy and still have abnormal blood tests. Blood work must be interpreted in context, considering your history, lifestyle, and physical exam. Numbers alone don’t tell the whole story. Always consult your doctor before assuming the worst.

So, before you let a red flag on your report worry you, talk to your doctor. You’re more than your lab values.

References:

1. Solberg, H. E. “Establishment and Use of Reference Values.” Toxicology Letters, 2004. https://doi.org/10.1016/j.toxlet.2004.04.033.

2. Ko, Dennis T., et al. “The Diagnostic Cascade.” BMJ 375 (2021): n2385. https://www.bmj.com/content/375/bmj.n2385.

3. Bartlett, W. A., et al. “Biological Variation in Lab Tests.” Annals of Clinical Biochemistry, 2012. https://doi.org/10.1258/acb.2012.011204.

4. Watson, J., et al. “Use of Blood Tests in Primary Care to Identify People at Risk of Cancer.” BMJ Open 9, no. 9 (2019): e025503. https://bmjopen.bmj.com/content/9/9/e025503.

By Dr. Varshini KR

^MSM/DP