Reading Your Bloodwork: What Biomarkers Actually Matter

Standard lab reference ranges are built for population health, not individual optimization. A "normal" result means you are within the range that encompasses roughly 95% of the tested population - a population that is, in many respects, metabolically compromised. For someone pursuing proactive health optimization, normal and optimal are different targets entirely.

This guide covers the biomarkers that matter most, the distinction between reference ranges and optimal ranges, and how to use bloodwork intelligently when running any protocol.

The Core Panel: What to Test Minimum

If you are running any peptide or biohacking protocol and doing only one blood draw, it should cover the following:

Biomarker	Standard Reference Range	Optimal Range (Performance)	Why It Matters
IGF-1	75-310 ng/mL (age-dependent)	150-250 ng/mL (adult)	Primary proxy for GH axis activity; affected by GH peptides
hsCRP	<10 mg/L	<1.0 mg/L	High-sensitivity inflammation marker; tracks recovery and systemic inflammation
Total Testosterone	264-916 ng/dL (male)	600-900 ng/dL (male, subjective)	Key anabolic hormone; influenced by stress, sleep, body composition
Free Testosterone	9-30 ng/dL (male)	20-30 ng/dL (male)	Biologically active fraction; more relevant than total in many cases
Cortisol (AM fasting)	6-23 mcg/dL	10-18 mcg/dL (AM)	Stress response axis; elevated chronically = catabolism, immune suppression
Fasting Insulin	<25 mIU/L	<6 mIU/L	Insulin resistance marker; elevated = poor metabolic health independent of glucose
Fasting Glucose	70-99 mg/dL	72-90 mg/dL	Metabolic baseline; GH peptides can affect insulin sensitivity
HbA1c	<5.7%	<5.2%	3-month glucose average; important baseline for GH-axis protocols
ALT (SGPT)	7-56 U/L	<25 U/L	Liver enzyme; screen for hepatic stress on any protocol
AST (SGOT)	10-40 U/L	<25 U/L	Liver + muscle enzyme; elevates with intense training, hepatic stress
LDL-C	<100 mg/dL	Context-dependent	Cardiovascular risk; GH optimization affects lipid panels
HDL-C	>40 mg/dL (male)	>55 mg/dL	Cardioprotective; tracks metabolic health quality

IGF-1: The Most Important Marker for Peptide Protocols

If you are running any GH-axis peptide - CJC-1295, Ipamorelin, Sermorelin, MK-677 - IGF-1 is your primary outcome biomarker. GH itself is impractical to measure meaningfully in most clinical settings because it is pulsatile; a single draw captures only a snapshot of a rapidly fluctuating value. IGF-1 is produced in the liver in response to cumulative GH exposure and has a half-life of 12-15 hours, making it a stable indicator of overall GH axis activity.

How to interpret changes:

• A 4-6 week protocol with CJC-1295/Ipamorelin should produce a measurable IGF-1 increase if dosed correctly
• No change in IGF-1 suggests subtherapeutic dosing, poor peptide quality, poor injection technique, or non-response
• IGF-1 above 300 ng/mL (in adults) warrants reassessment of dose; values persistently above this range are associated with increased proliferative risk in long-term epidemiological data

Cortisol: The Underappreciated Blocker

Chronically elevated cortisol is one of the most common reasons peptide protocols underperform. Cortisol is catabolic, suppresses GH secretion, impairs tissue repair, and antagonizes testosterone. An elevated AM cortisol (above 20 mcg/dL consistently) indicates either genuine chronic stress load, HPA axis dysregulation, or poor sleep quality.

No amount of peptide optimization will overcome a cortisol problem. If your AM cortisol is persistently elevated, address the root cause (sleep, stress, nutrition) before layering in protocols.

Cortisol patterns to know:

• AM cortisol should be at peak (highest of the day); PM cortisol should be low (<5 mcg/dL)
• An inverted pattern (low AM, elevated PM) suggests circadian rhythm disruption - common with shift work, late-night screens, or alcohol use
• Four-point salivary cortisol testing gives a more complete picture than a single serum draw

Inflammatory Markers: Tracking Systemic State

hsCRP (High-Sensitivity C-Reactive Protein)

hsCRP is the most sensitive and accessible general inflammation marker. Standard CRP catches acute inflammation; hsCRP captures the chronic low-grade inflammation that underlies most metabolic disease and accelerated aging. Many labs report CRP without the high-sensitivity assay - confirm you are getting hsCRP specifically.

For anyone running a healing protocol (BPC-157, TB-500), a baseline hsCRP provides context for the inflammatory state you are working with and allows you to track whether the protocol is producing measurable systemic anti-inflammatory effects over time.

Erythrocyte Sedimentation Rate (ESR)

A less sensitive but complementary inflammation marker. More useful for tracking chronic inflammatory conditions than acute state.

Liver Enzymes: Non-Negotiable Safety Monitoring

Any protocol you run longer than 4 weeks should include a liver panel. ALT and AST are the primary hepatic enzymes to monitor. Isolated ALT elevation suggests hepatic stress; combined ALT/AST elevation with elevated bilirubin or GGT indicates more significant hepatic involvement.

Important context: AST elevates with muscle damage from intense training, independent of liver status. If you train hard, an isolated AST elevation without corresponding ALT elevation is likely muscular, not hepatic.

Testing Frequency and Timing

Protocol Type	Recommended Testing	Timing
GH-axis peptides (CJC/Ipamorelin, MK-677)	IGF-1, fasting glucose, HbA1c, liver panel	Baseline + 6 weeks in + end of cycle
Healing peptides (BPC-157, TB-500)	hsCRP, ESR, liver panel	Baseline + end of cycle (6-8 weeks)
Any protocol (standard monitoring)	Full metabolic panel + CBC	Minimum quarterly
Hormonal protocols	Full hormone panel, SHBG, LH, FSH, prolactin	Baseline, 6 weeks, end of cycle

How to Collect Properly

Bloodwork accuracy depends heavily on collection conditions:

• Fast for 10-12 hours before any metabolic panel (glucose, insulin, lipids)
• AM collection (7-9am) is essential for cortisol and GH-related markers
• Avoid intense exercise for 48 hours before testing - this affects AST, CPK, and can transiently affect testosterone and IGF-1
• Consistent timing between tests - if you test at 8am on cycle, test at 8am off cycle. Variation in collection time creates noise in the data
• Hydration matters - mild dehydration concentrates blood markers and can make results appear falsely elevated

Red Flags That Warrant Pausing Any Protocol

• ALT or AST more than 3x the upper limit of normal
• IGF-1 above 350 ng/mL (adults) without intentional high-dose protocol under medical supervision
• Fasting glucose above 110 mg/dL if previously normal (GH peptides can induce transient insulin resistance)
• HbA1c increase of more than 0.3% from baseline
• Testosterone below 200 ng/dL without prior history (may indicate hypothalamic-pituitary suppression from exogenous compounds)
• Any new symptoms not present at baseline that coincide with protocol start

The Tracking Mindset

Bloodwork is not a compliance exercise. It is the primary feedback mechanism that distinguishes systematic self-optimization from uncontrolled self-experimentation. Treat your blood data the way you would any other dataset: collect rigorously, interpret conservatively, and change only one variable at a time so you can actually learn from the results.