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Biomarkers

Understanding blood tests and health markers—what they measure, optimal ranges, and how to interpret your results.

📖 The Story​

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Marcus got his annual physical results back: "All normal." His doctor said everything looked fine and scheduled next year's visit. But Marcus didn't feel fine. He was tired, gaining weight despite eating well, and his brain felt foggy.

On a whim, he took his results to a functional medicine practitioner. She looked at the same numbers and told a different story.

"Your fasting glucose is 99—technically normal, but at the high end. Your vitamin D is 28—'normal range' but suboptimal. Your thyroid TSH is 3.8—normal range but I'd like it lower. Your LDL is fine but your triglyceride-to-HDL ratio suggests insulin resistance."

Nothing was flagged as abnormal, but the pattern told a story of metabolic dysfunction in its early stages. With targeted interventions—not medications, just lifestyle optimization—Marcus's markers improved. So did his energy, weight, and mental clarity.

"My regular doctor was looking for disease," Marcus realized. "She was looking for optimization. Same numbers, different questions."

The lesson: Normal isn't optimal. Understanding your biomarkers—not just whether they're flagged—empowers you to optimize health before problems develop.

🚶 The Journey​

The Biomarker Framework

Lab Normal vs. Optimal:

BiomarkerLab "Normal"Optimal RangeWhy It Matters
Fasting glucose65-99 mg/dL70-85 mg/dLEarly insulin resistance detection
TSH0.4-4.5 mIU/L1.0-2.5 mIU/LSubclinical thyroid issues
Vitamin D30-100 ng/mL50-80 ng/mLImmune function, mood
Ferritin15-150 ng/mL (varies)50-150 ng/mLIron status nuance

"Normal" often means "not diseased"—not "optimal."

🧠 The Science​

Understanding Biomarkers

What Biomarkers Tell Us​

Categories of Blood Tests:

CategoryWhat It MeasuresExamples
Metabolic panelGlucose, kidney, electrolytesBMP, CMP
Lipid panelCholesterol, triglyceridesTotal, LDL, HDL, TG
Complete blood countBlood cellsRBC, WBC, hemoglobin
Thyroid panelThyroid functionTSH, T3, T4
Inflammatory markersInflammationCRP, ESR
Nutrient levelsVitamins, mineralsD, B12, iron
Hormone panelsHormonal statusTestosterone, estrogen

Why Reference Ranges Vary​

Factors affecting "normal":

  • Based on population averages (often unhealthy population)
  • Lab-specific variations
  • Statistical rather than health-based (95% of people)
  • Don't account for age, sex, individual variation
  • Updated infrequently

Optimal vs. Normal:

  • Normal = not flagged as abnormal
  • Optimal = associated with best health outcomes
  • Goal should be optimal, not just normal
  • Patterns matter as much as individual values

Key Principles​

Context Matters:

  • Single values less meaningful than trends
  • Consider symptoms, not just numbers
  • Time of day, fasting status, stress affect results
  • Other markers inform interpretation
  • Individual variation exists

Ratios Often More Informative Than Single Values:

  • Triglyceride/HDL ratio (insulin resistance)
  • BUN/Creatinine ratio (hydration, kidney function)
  • T3/T4 ratio (thyroid conversion)
  • Neutrophil/lymphocyte ratio (inflammation, stress)
## 👀 Signs & Signals

When to Test Biomarkers​

Routine Testing:

  • Annual comprehensive panel
  • More frequent if optimizing or monitoring condition
  • Before starting new intervention
  • When something feels "off"

Specific Symptoms to Investigate:

SymptomConsider Testing
FatigueThyroid, iron, B12, glucose
Weight gainThyroid, fasting insulin, lipids
Brain fogThyroid, B12, glucose, inflammation
Hair lossThyroid, iron, testosterone
DepressionThyroid, vitamin D, inflammation
Muscle weaknessVitamin D, magnesium, electrolytes
Cold intoleranceThyroid (full panel)
Frequent illnessVitamin D, CBC, zinc

Signs Your Numbers Need Attention​

Even if "normal":

  • Values near high or low end of range
  • Significant change from previous tests
  • Symptoms despite "normal" results
  • Pattern across multiple markers
  • Values moving in wrong direction over time

🎯 Practical Application​

Using Biomarkers Effectively

Minimum Annual Panel​

Basic Metabolic:

  • Fasting glucose (and ideally fasting insulin)
  • Comprehensive metabolic panel (kidney, liver, electrolytes)

Lipids:

  • Total cholesterol, LDL, HDL, triglycerides
  • Consider advanced lipid panel if concerned

Thyroid:

  • TSH (minimum)
  • Better: TSH, Free T4, Free T3, TPO antibodies

Blood Count:

  • Complete blood count with differential

Inflammation:

  • High-sensitivity CRP (hs-CRP)

Nutrients:

  • Vitamin D (25-OH)
  • Vitamin B12
  • Iron panel (ferritin, serum iron, TIBC)

This basic panel catches most significant issues.

## 📸 What It Looks Like

Sample Annual Protocol​

Timing:

  • Morning (7-10 AM)
  • Fasted 12-14 hours
  • Well-hydrated (water okay)
  • Avoid intense exercise 24 hours before
  • Note menstrual cycle day if relevant

Basic Panel:

  • Comprehensive metabolic panel
  • Lipid panel
  • CBC with differential
  • TSH (or full thyroid)
  • hs-CRP
  • Vitamin D
  • Vitamin B12
  • Ferritin

Additional If Optimizing:

  • Fasting insulin
  • HbA1c
  • Homocysteine
  • Full thyroid panel

Tracking Your Numbers​

BiomarkerReferenceMy OptimalLast TestTrend
Fasting glucose65-9970-85___↑↓→
HbA1c<5.7%<5.4%___↑↓→
Triglycerides<150<100___↑↓→
HDL>40 M, >50 F>60___↑↓→
Vitamin D30-10050-80___↑↓→
TSH0.4-4.51.0-2.5___↑↓→
## 🚀 Getting Started

Step 1: Get Baseline Tests​

  • Schedule annual physical with comprehensive labs
  • Request additions beyond basic (vitamin D, iron panel)
  • Fast 12-14 hours, morning draw
  • Request copy of results (not just "normal/abnormal")

Step 2: Review Results​

  • Note any flagged abnormal values
  • Compare to optimal ranges (not just lab ranges)
  • Calculate key ratios
  • Identify patterns

Step 3: Research and Prioritize​

  • Learn what each marker means
  • Identify most impactful areas to address
  • Research evidence-based interventions
  • Decide what to discuss with provider

Step 4: Implement and Retest​

  • Make targeted lifestyle changes
  • Allow 3-6 months for changes to show
  • Retest relevant markers
  • Track progress over time

Ongoing​

  • Annual comprehensive testing
  • More frequent for markers being actively managed
  • Build personal database of results
  • Partner with informed provider
## 🔧 Troubleshooting

Common Biomarker Challenges​

"My doctor says everything is normal but I feel terrible"

  • Normal ≠ optimal
  • Ask for copies and research optimal ranges
  • Consider functional medicine evaluation
  • Look for patterns across markers
  • Trust your symptoms

"My results are confusing"

  • Focus on flagged items first
  • Learn one category at a time
  • Use reliable resources
  • Consider health coach or informed provider
  • Context matters—one snapshot isn't everything

"Results vary between tests"

  • Normal variation exists
  • Check timing (time of day, fasting)
  • Consider stress, sleep, illness
  • Trends matter more than single values
  • Lab variation between companies

"I can't afford comprehensive testing"

  • Prioritize most impactful tests
  • Insurance often covers basics
  • Direct-to-consumer labs can be cheaper
  • Annual physical usually covered
  • Focus on what you can do

"My doctor won't order what I want"

  • Explain your reasoning
  • Ask if there's a reason against it
  • Direct-to-consumer options exist
  • Find more collaborative provider
  • Some tests require interpretation—partnership helps
## 🤖 For Mo

AI Coach Guidance​

Assessment Questions:

  1. "When was your last comprehensive blood test?"
  2. "What specific health concerns are you investigating?"
  3. "Do you have access to your actual numbers (not just normal/abnormal)?"
  4. "What markers are most important to you right now?"
  5. "Are you working with a provider on this?"

Key Coaching Points:

  • Biomarkers are tools for optimization
  • Normal vs. optimal matters
  • Patterns and trends matter as much as single values
  • Lifestyle can significantly impact most markers
  • Partner with healthcare provider

Important Boundaries:

  • Cannot diagnose conditions
  • Cannot interpret results as medical advice
  • Recommend working with qualified provider
  • Education about markers, not diagnosis

Example Scenarios:

  1. "What tests should I get?":

    • Suggest comprehensive baseline panel
    • Ask about specific concerns
    • Explain categories of tests
    • Recommend discussing with provider

  2. "My vitamin D is 28—is that okay?":

    • Explain lab normal vs. optimal
    • Research suggests 50-80 ng/mL is optimal
    • Supplementation often helpful
    • Retest after 3 months
    • Not medical advice—discuss with provider

  3. "How do I lower my inflammation?":

    • Explain what inflammatory markers measure
    • Lifestyle interventions (diet, sleep, stress)
    • Find root cause if possible
    • Work with provider to monitor
## ❓ Common Questions

Q: How often should I get blood tests? A: Annual comprehensive testing is baseline. More frequent (every 3-6 months) if actively optimizing or managing a condition. Some markers (like vitamin D after supplementation) should be rechecked to ensure you're in range.

Q: Do I need a doctor to order labs? A: For many tests, direct-to-consumer services allow ordering without a doctor. However, interpretation and treatment recommendations benefit from working with a qualified provider. Some tests (hormones, advanced panels) may require physician ordering.

Q: What affects test accuracy? A: Fasting status, time of day, recent exercise, stress, sleep, hydration, medications, supplements, menstrual cycle, and lab variation all affect results. Follow preparation instructions and note circumstances.

Q: Why do different labs have different reference ranges? A: Labs use different equipment, methodologies, and reference populations. This is why tracking with the same lab over time is helpful. Optimal ranges are more consistent across sources.

Q: Should I stop supplements before testing? A: Depends on the goal. To see true baseline, stop supplements affecting that marker (B12 before B12 test, for example). To see if supplementation is working, continue as normal. Discuss with provider.

## ✅ Quick Reference

Essential Biomarker Ranges​

MarkerLab "Normal"OptimalNotes
Fasting glucose65-99 mg/dL70-85>90 = watch trend
HbA1c<5.7%<5.4%Reflects 3-month average
Fasting insulin2-20 μIU/mL2-8Often not tested—request it
Triglycerides<150 mg/dL<100Carb intake marker
HDL>40 (M), >50 (F)>60Higher is better
LDL<100 mg/dLVariesContext dependent
TSH0.4-4.5 mIU/L1.0-2.5Full thyroid more informative
Vitamin D30-100 ng/mL50-80Most people deficient
Vitamin B12200-900 pg/mL500-900Low-normal may have symptoms
Ferritin15-150 ng/mL50-150Too high or low problematic
hs-CRP<3.0 mg/L<1.0Lower = less inflammation

Test Preparation​

PreparationWhy
Fast 12-14 hoursAccurate glucose, lipids, insulin
Morning drawConsistent timing for comparison
Hydrate (water)Accurate kidney markers
No intense exercise 24hCan affect inflammation
Note menstrual dayAffects hormones

💡 Key Takeaways​

Essential Insights
  1. Normal isn't optimal—lab ranges catch disease, not optimization
  2. Request your actual numbers—not just normal/abnormal
  3. Patterns matter—look at multiple markers together
  4. Track over time—trends more valuable than snapshots
  5. Context matters—timing, stress, fasting all affect results
  6. Lifestyle changes work—most markers respond to diet, sleep, exercise
  7. Partner with providers—interpretation benefits from expertise
## 📚 Sources
  • American Association for Clinical Chemistry Lab Test Guidelines Tier A
  • Attia, Peter - "Outlive" (longevity biomarkers) Tier C
  • Institute for Functional Medicine - Optimal Ranges Tier B
  • Metabolic Health Research (insulin resistance markers) Tier A
  • Cardiovascular Risk Markers Meta-analyses Tier A

🔗 In This Section​