Longevity and Labs – Why "Normal" Isn’t Always Optimal
You don’t want to be “normal” in a society where normal is sick.
When you get your labs drawn at the doctor’s office, you’re often told one of two things: “You’re normal” or “Something’s wrong.” But here’s the truth—normal doesn’t always mean healthy. In fact, “normal” is just an average of the population. And in today’s world, where chronic illness, obesity, and metabolic dysfunction are common, “normal” ranges reflect a society that’s getting sicker—not healthier.
That’s why it’s important to understand the difference between normal labs and optimal labs.
Normal vs. Optimal: What’s the Difference?
Normal lab ranges are created using statistical averages of the population. If your results fall within that bell curve, you’re considered “normal.”
Optimal ranges are where people actually thrive—labs that reflect healthy metabolism, energy, fertility, cognition, and longevity.
Being “normal” might mean you don’t have a diagnosable disease yet, but it doesn’t mean you’re functioning at your best.
Why Lab Ranges Have Shifted Over Time
Over the decades, lab ranges have been quietly lowered. Why? Because as populations become sicker, the average shifts. For example:
Rising rates of insulin resistance and diabetes have nudged blood sugar “normal” higher.
Vitamin deficiencies are widespread, so the “normal” bar is set low.
Thyroid disease and autoimmune disorders are more common, yet many people remain undiagnosed because their results fall just inside the “normal” cutoff.
This means you could be told you’re “fine,” even while experiencing fatigue, brain fog, infertility, or weight gain—because you haven’t crossed the line into disease yet.
Common Labs: Normal vs. Optimal Ranges
Lab Test Normal Range Optimal Range
Fasting Glucose 70–99 mg/dL 75–85 mg/dL
HbA1c <5.6% 4.8–5.2%
Vitamin D (25-OH) 30–100 ng/mL 50–70 ng/mL
TSH (Thyroid) 0.5–4.5 μIU/mL 1.0–2.0 μIU/mL
Free T3 2.0–4.4 pg/mL 3.2–4.2 pg/mL
LDL-C <130 mg/dL <100 mg/dL (or ApoB <90 mg/dL)
hs-CRP <3.0 mg/L <1.0 mg/L
(Ranges may vary slightly by lab; functional/optimal ranges are based on research and clinical outcomes rather than averages.)
Patient Story: “Normal” but Struggling
Sarah, a 34-year-old teacher, came to me after months of fatigue, weight gain, and difficulty conceiving. Her primary care doctor told her everything looked “normal.”
When we reviewed her labs together, we noticed:
Fasting glucose at 96 mg/dL (normal but not optimal).
Vitamin D at 31 ng/mL (just barely “in range”).
TSH at 3.9 μIU/mL (within the normal 0.5–4.5 range, but high for thyroid function).
Here’s where it gets interesting: reproductive endocrinologists often prefer a TSH of 2.5 or less for women trying to conceive. Even though Sarah’s doctor reassured her she was “normal,” her thyroid function was outside the optimal fertility range.
With targeted nutrition, supplements, and lifestyle shifts, Sarah lowered her fasting glucose into the 80s, raised vitamin D into the 50s, and brought her TSH under 2.5. Within six months, she had more energy, her cycles improved, and she felt hopeful again on her fertility journey.
Why Optimal Matters: Evidence and Outcomes
Fasting Blood Glucose: Studies show people with fasting glucose above 90 mg/dL are more likely to develop type 2 diabetes within 10 years—even if they’re still “normal” today.
Vitamin D: The optimal 50–70 ng/mL range is not only best for bone and immune health—it’s where both men and women should aim to be before conception, supporting fertility, hormone balance, and cellular health for both parent and child.
Why Early Dysfunction Is Missed
Traditional medicine is designed to detect disease, not optimize health. Doctors are trained to treat you when you cross into diabetes, hypothyroidism, or deficiency—but not to intervene earlier. This “wait until it’s broken” approach misses opportunities for prevention, longevity, and feeling your best.
Interpreting Labs Through a Longevity Lens
Looking at your labs through a functional and longevity-based approach allows you to:
Spot trends before they become diagnoses.
Fine-tune nutrition, lifestyle, and supplementation for prevention.
Track improvements over time instead of waiting for decline.
Empower yourself with data that helps you feel in control of your health.
How to Find Optimal Ranges
Functional medicine practitioners, nurse coaches, and longevity specialists often use research-backed optimal ranges instead of “just normal.” Resources include:
Published studies on disease prevention and longevity.
Functional medicine reference ranges.
Coaching tools that track labs alongside symptoms, nutrition, and lifestyle.
Working with a functional nurse coach helps you not only understand your labs, but also create personalized, sustainable strategies to move your results into the optimal zone—so you don’t just avoid disease, you build a foundation for long-term health.
Final Thought
The next time you’re told your labs are “normal,” remember: normal doesn’t always mean optimal. If your goal is longevity, energy, fertility, and vibrant health—you want to be better than normal.
