Beyond "Normal" Ranges
When your doctor says your labs are "normal," what does that actually mean? Normal ranges are set so that 95% of the population falls within them—including people who are sick, sedentary, or metabolically unhealthy.
"Normal" doesn't mean optimal. A testosterone level of 300 ng/dL is technically "normal" for a 35-year-old man, but it's the same level you'd expect in an 80-year-old. You can be in the "normal" range and still feel terrible.
This guide will help you understand what your numbers actually mean and what optimal levels look like.
Hormone Markers
Total Testosterone
Lab "Normal" Range (Men)
264–916 ng/dL
Optimal Range (Men)
600–900 ng/dL
What it measures: Total amount of testosterone in blood, including both bound and unbound.
Why it matters: Testosterone affects energy, mood, libido, muscle mass, fat distribution, bone density, and cognitive function.
Key insight: Where you fall within the range matters. A level of 350 might be "normal" but can cause significant symptoms. Context matters—age, symptoms, and free testosterone levels all factor in.
Free Testosterone
Lab "Normal" Range (Men)
9–30 pg/mL
Optimal Range (Men)
15–25 pg/mL
What it measures: The testosterone not bound to proteins—the portion that's actually available for your body to use.
Key insight: You can have "normal" total testosterone but low free testosterone if SHBG (sex hormone binding globulin) is high. Free T is often more clinically relevant than total T.
Estradiol (E2)
Lab "Normal" Range (Men)
10–40 pg/mL
Optimal Range (Men)
20–35 pg/mL
What it measures: The primary estrogen hormone. Men need some estrogen for bone health, libido, and cardiovascular function.
Key insight: Both high and low estradiol cause problems. High E2 can cause water retention, mood issues, and gynecomastia. Low E2 causes joint pain, low libido, and mood issues. Balance with testosterone matters.
SHBG (Sex Hormone Binding Globulin)
Lab "Normal" Range
10–57 nmol/L
Optimal Range
20–40 nmol/L
What it measures: A protein that binds to sex hormones. High SHBG = less free hormone available.
Key insight: High SHBG can make your total testosterone look fine while you're functionally low. Elevated by: aging, high estrogen, liver issues, hyperthyroidism. Lowered by: insulin resistance, obesity, hypothyroidism.
Thyroid Markers
TSH (Thyroid Stimulating Hormone)
Lab "Normal" Range
0.4–4.5 mIU/L
Optimal Range
1.0–2.0 mIU/L
What it measures: A pituitary hormone that tells your thyroid to produce hormones. Counterintuitively, HIGH TSH = LOW thyroid function (your body is screaming for more thyroid hormone).
Key insight: Many people with TSH of 3-4 have subclinical hypothyroidism—technically "normal" but experiencing fatigue, weight gain, and brain fog. TSH alone doesn't tell the full story; you need Free T3 and T4 as well. For a deeper look at thyroid optimization, see our full guide.
Free T3
Lab "Normal" Range
2.3–4.2 pg/mL
Optimal Range
3.0–4.0 pg/mL
What it measures: The active thyroid hormone. T4 converts to T3, which is what your cells actually use.
Key insight: Many people have normal T4 but poor conversion to T3. Stress, nutrient deficiencies (selenium, zinc, iron), and inflammation can all impair conversion. Free T3 is often the most clinically relevant thyroid marker.
Free T4
Lab "Normal" Range
0.8–1.8 ng/dL
Optimal Range
1.2–1.5 ng/dL
What it measures: The storage form of thyroid hormone. Your body converts T4 to T3 as needed.
Key insight: If TSH and T4 look normal but you still have symptoms, check T3 and reverse T3. Poor T4-to-T3 conversion is common.
Metabolic Markers
Fasting Glucose
Lab "Normal" Range
65–99 mg/dL
Optimal Range
70–85 mg/dL
What it measures: Blood sugar after 10-12 hours of fasting.
Key insight: A fasting glucose of 95 is "normal" but indicates insulin resistance is likely developing. By the time glucose hits 100+, you've had insulin problems for years. Pair with fasting insulin for the full picture.
Fasting Insulin
Lab "Normal" Range
2–25 μIU/mL
Optimal Range
3–8 μIU/mL
What it measures: How much insulin your pancreas produces to control blood sugar.
Key insight: Often the FIRST marker to become abnormal in metabolic dysfunction—years before glucose rises. High fasting insulin (above 10) with normal glucose = insulin resistance. Your body is working overtime to keep glucose normal.
HbA1c (Hemoglobin A1c)
Lab "Normal" Range
4.0–5.6%
Optimal Range
4.5–5.2%
What it measures: Average blood sugar over the past 2-3 months. Reflects how much glucose has "stuck" to red blood cells.
Key insight: More stable than fasting glucose (not affected by yesterday's pizza). An A1c of 5.5% is "normal" but associated with increased cardiovascular risk compared to 5.0%. Prediabetes starts at 5.7%.
Lipid Panel
The Old vs New Understanding
The old model: "High cholesterol = heart disease." The new understanding: Lipids are more nuanced. Total cholesterol alone is nearly meaningless. What matters is the size and number of LDL particles, triglyceride/HDL ratio, and inflammatory markers. Context matters.
Triglycerides
Lab "Normal" Range
<150 mg/dL
Optimal Range
<100 mg/dL (ideally <70)
What it measures: Fat in your blood, largely driven by carbohydrate intake and insulin resistance.
Key insight: Triglycerides are more responsive to diet than LDL. High triglycerides + low HDL = metabolic syndrome pattern. Often improves dramatically with carbohydrate reduction.
HDL Cholesterol
Lab "Normal" Range
>40 mg/dL (men), >50 (women)
Optimal Range
>50 mg/dL (men), >60 (women)
What it measures: "Good" cholesterol that helps transport cholesterol away from arteries.
Key insight: HDL is protective. Low HDL is often a sign of metabolic dysfunction. Exercise, moderate alcohol, and healthy fats raise HDL. The triglyceride/HDL ratio is a useful proxy for insulin resistance (optimal <2.0).
LDL Cholesterol
Lab "Normal" Range
<100 mg/dL
Optimal Range
Context-dependent
What it measures: Usually calculated, not measured directly. Represents the cholesterol carried by LDL particles.
Key insight: LDL-C (cholesterol content) is less predictive than LDL-P (particle number) or ApoB. You can have low LDL-C but high particle number (more atherogenic) or vice versa. Advanced lipid testing provides more actionable data.
Inflammation & Other Markers
hsCRP (High-Sensitivity C-Reactive Protein)
Lab "Normal" Range
<3.0 mg/L
Optimal Range
<1.0 mg/L
What it measures: A marker of systemic inflammation. Produced by the liver in response to inflammation anywhere in the body.
Key insight: Elevated hsCRP is associated with increased cardiovascular risk independent of cholesterol. Can be elevated by acute infection, chronic disease, obesity, or metabolic dysfunction. Useful for tracking inflammation over time.
Vitamin D (25-OH)
Lab "Normal" Range
30–100 ng/mL
Optimal Range
50–70 ng/mL
What it measures: Your vitamin D status. Actually a hormone precursor, not just a vitamin.
Key insight: Deficiency is extremely common, especially in northern latitudes. Low vitamin D is linked to immune dysfunction, mood issues, fatigue, and increased disease risk. Most people need supplementation to reach optimal levels.
Ferritin
Lab "Normal" Range
12–300 ng/mL (men)
Optimal Range
50–150 ng/mL
What it measures: Iron stores. Low ferritin = depleted iron. Very high ferritin can indicate iron overload or inflammation.
Key insight: Low ferritin causes fatigue even with "normal" hemoglobin. Common in menstruating women and endurance athletes. Very high ferritin (>400) warrants further investigation for hemochromatosis or chronic inflammation.
Common Patterns to Watch For
Metabolic Syndrome Pattern
High triglycerides (>150), low HDL (<40 men/<50 women), elevated fasting glucose (>100), high insulin (>10). Often with elevated hsCRP. This pattern precedes type 2 diabetes by years.
Subclinical Hypothyroid Pattern
TSH 2.5–4.5 (technically "normal"), low-normal Free T3, fatigue, weight gain, cold intolerance, brain fog. Often dismissed as "normal" despite clear symptoms.
High SHBG Pattern (Men)
Total testosterone looks fine (500-700), but free testosterone is low (<10 pg/mL) due to elevated SHBG. Symptoms of low T despite "normal" total T. Often caused by aging, low-carb diets, or elevated estrogen.
Inflammation + Poor Metabolic Health
Elevated hsCRP (>2), high triglycerides, high insulin, elevated LDL-P. This combination significantly increases cardiovascular risk even if LDL-C looks okay.
What To Do With This Information
Understanding your labs is the first step. The next step is working with a provider who interprets them in context—looking at patterns, symptoms, and your goals rather than just checking boxes.
At Moonshot, we run comprehensive panels and take the time to explain what each marker means for YOU. We aim for optimal, not just "normal."
If you've been told your labs are "fine" but you still don't feel right, you're not crazy. The numbers tell a story—you just need someone willing to read the whole thing.
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