Biomarker Profiles

Reference vs optimal ranges for the biomarkers most commonly tracked on peptide, GLP-1, and optimization protocols. Each guide covers what the marker measures, what moves it, and which compounds reliably change it.

GROWTH

IGF-1

Insulin-like Growth Factor 1

The primary downstream mediator of growth hormone, and the main lab marker used to monitor GH secretagogue protocols.

Optimal: Upper quartile for age — typically 180–240 ng/mL for ages 30–50

CARDIOVASCULAR

ApoB

Apolipoprotein B

The single most accurate serum marker of atherosclerotic cardiovascular risk — more predictive than LDL-C.

Optimal: <80 mg/dL (general population); <60 mg/dL (existing CVD or high risk)

HORMONE

Total Testosterone

Total Testosterone

The most commonly measured hormone in men — but rarely the most informative without the context of SHBG and free testosterone.

Optimal: 500–900 ng/dL is a common target in optimization practice

Estradiol

Estradiol (E2) — Sensitive Assay

The primary estrogen in both sexes. In men, tight tracking matters on testosterone-modulating protocols to catch both excess and deficiency.

Optimal: Men: 20–35 pg/mL on TRT; premenopausal women: phase-dependent

METABOLIC

HbA1c

Glycated Hemoglobin (A1C)

Reflects average blood glucose over the prior ~90 days — the gold-standard measure of chronic glycemic control.

Optimal: <5.4% (metabolic optimization target)

INFLAMMATION

hs-CRP

High-Sensitivity C-Reactive Protein

The most commonly used marker of low-grade systemic inflammation and cardiovascular risk.

Optimal: <1.0 mg/L — often <0.5 mg/L in highly optimized individuals

Track all of them in one place.

Upload any lab PDF — MyProtocolStack auto-extracts values and maps them to 40+ tracked biomarkers. StackAI reads the panel in context of your protocol.

Start tracking →

Informational only — not medical advice. Reference ranges vary by lab and individual context. Work with a licensed provider to interpret your specific results.