How to Read Blood Test Results (Without a Medical Degree)

You get your blood test results back. There are 30+ numbers, each with a reference range, some flagged with arrows. Your doctor spends 2 minutes going over them. What do they all actually mean?

The basics: what you’re looking at

Every lab report has the same structure:

1. Test name — what was measured (e.g., “Ferritin”, “TSH”, “Glucose”)
2. Your value — the number the lab found
3. Reference range — what’s “normal” for your age and sex
4. Units — how it’s measured (ng/mL, mIU/L, mg/dL, etc.)
5. Flag — arrow up (high), arrow down (low), or nothing (normal)

The most important numbers to know

Ferritin (iron storage)

• What it measures: How much iron your body has stored
• Normal range: 12-300 ng/mL (varies by sex)
• Optimal: 40-100 ng/mL
• Why it matters: Low ferritin = fatigue, brain fog, hair loss. High ferritin = inflammation or iron overload.

TSH (thyroid)

• What it measures: How hard your thyroid is working
• Normal range: 0.4-4.0 mIU/L
• Optimal: 0.5-2.5 mIU/L
• Why it matters: High TSH = possible hypothyroidism. Low TSH = possible hyperthyroidism.

HbA1c (blood sugar average)

• What it measures: Average blood sugar over 3 months
• Normal range: Below 5.7%
• Prediabetes: 5.7-6.4%
• Diabetes: 6.5%+
• Why it matters: Most accurate long-term sugar marker. More reliable than fasting glucose.

LDL Cholesterol

• What it measures: “Bad” cholesterol
• Normal range: Below 100 mg/dL (optimal)
• Why it matters: High LDL = increased cardiovascular risk.

Vitamin D

• What it measures: Vitamin D level
• Normal range: 30-100 ng/mL
• Optimal: 40-60 ng/mL
• Why it matters: Low vitamin D = weak bones, poor immune function, mood issues.

What “normal” actually means

Here’s the important part: normal range ≠ optimal range.

Your lab says your ferritin of 25 is “normal” (range starts at 12). But research suggests ferritin below 30 can cause symptoms. Your doctor might say “it’s fine” — but you feel tired all the time.

This is why tracking over time matters more than any single number. A ferritin of 25 that was 85 six months ago tells a different story than a ferritin of 25 that’s been stable for years.

What to do with your results

1. Don’t panic. Most flags are minor and temporary.
2. Look at trends. One result is a snapshot. Three results over 12 months is a story.
3. Connect to symptoms. If your ferritin is low AND you’re tired — that’s a pattern.
4. Ask your doctor. “Should we retest in 3-6 months?” is always a good question.
5. Track them. Don’t let results sit in a folder. Put them somewhere you can find them.

Track your results with Bevita

Bevita uploads any lab result, extracts every value, tracks trends over time, and connects your biomarkers to your symptoms. When your doctor asks “how have your levels been?” — you have the answer.

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