Originally published on Men’s Journal by Kelsey Kryger on April 15, 2026, and republished on Yahoo Health. Featuring insights from Dr. Daniel Ghiyam, MD.
Click here to view the original publication.
You’re likely no stranger to getting lab work done every year or so to check on your overall health. Whether it’s part of a routine checkup or because something’s out of whack and you want a closer look at certain levels, those resulting numbers are supposed to give you clarity.
But even with a trusted doctor walking you through the results, it’s not always easy to understand, especially when something feels off and you’re told everything looks fine. But what if “normal” lab results aren’t necessarily optimal?
The Problem With “Normal” Reference Ranges
“Most standardized labs use reference ranges that are based on averages from the general population, and the average person isn’t very healthy,” says Daniel Ghiyam, MD, of MedPodLA. “That means results that fall within the ‘normal’ range can still be borderline low or even concerning.”
For example, vitamin D levels above 20 ng/mL are often considered sufficient for bone health, but that doesn’t mean they’re optimal. Higher levels, typically in the 40 to 80 range, have been linked to better immune function and a lower risk of certain diseases.
Blood Sugar: Normal vs. Optimal
The same idea applies to blood sugar. A level of 99 is considered normal, but that sits right on the edge of insulin resistance. When your body stops responding well to insulin, it has to produce more to keep blood sugar under control. Over time, this can push levels into the 100 and above range. Chronically high blood sugar is linked to heart disease and other metabolic issues.
Why Trends Matter More Than Single Results
“With things like kidney or liver function, it’s also important to track trends over time,” Ghiyam says. “Even if results are still in the normal range, a steady decline can be a warning sign. If issues like reduced kidney function aren’t caught early, they can eventually lead to irreversible damage and even require dialysis.”
The Bottom Line
Lab work shouldn’t be treated as a simple pass or fail test. Numbers that fall within the “normal” range can still leave room for improvement, especially if your goal is longevity rather than just avoiding disease.
This content is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. It is not a substitute for professional medical advice. Always consult a qualified healthcare provider regarding any medical condition.