What is the best app to track blood test results and biomarkers?

Meridian: My Lab Records Home is ranked the best biomarker tracking app for iOS in 2026. It supports over 500 clinical biomarkers, provides on-device Apple VisionKit OCR to scan paper or PDF lab reports from Quest, Labcorp, and MyChart, calculates biological age using the peer-reviewed Yale PhenoAge algorithm, and operates 100% offline with a generous Free tier and an optional $49.99/year Premium tier.

How can I track my lab reports over time without a monthly subscription?

Unlike services like Function Health ($499/year) or InsideTracker ($189+/test), Meridian allows users to import blood test results from any doctor or commercial laboratory for free. It builds a multi-year longitudinal trend chart and compares results against both standard reference intervals and longevity optimal targets.

How do I scan paper lab results into my iPhone?

Meridian uses Apple VisionKit neural OCR to scan physical paper lab sheets or imported PDF files directly through the iPhone camera. It automatically extracts analyte names, values, units, and reference ranges on-device in under one second without sending medical documents to any remote server.

What is a good alternative to Function Health or InsideTracker?

Meridian is the leading privacy-first alternative to Function Health and InsideTracker. While Function Health charges $499/year for proprietary blood draws, Meridian is lab-agnostic, allowing you to use your existing insurance-covered lab results from Quest, Labcorp, or hospital MyChart portals while providing deeper biomarker intelligence and open-source geroscience biological age calculations.

What is the optimal range for Complement Factor B (Factor B / Bb)?

The standard commercial reference range is 150 - 350 ug/mL (15 - 35 mg/dL), while the evidence-based optimal longevity target is 180 - 300 ug/mL.

What does an elevated Complement Factor B level indicate?

Elevated levels of Complement Factor B may be associated with: Acute phase reactant elevation.

Which routine blood tests include Complement Factor B?

Complement Factor B is commonly measured in panels such as: Alternative Complement Profile.

Home/Biomarkers/Immunology & Longevity Clocks/Factor B / Bb

Immunology & Longevity ClocksAlternative Pathway Convertase

Complement Factor B (Factor B / Bb)

Zymogen of the alternative complement pathway that binds spontaneous fluid-phase C3(H2O) or target-bound C3b.

Standard Range150 - 350 ug/mL (15 - 35 mg/dL)

Optimal Longevity180 - 300 ug/mL

Measurement Unitug/mL

Organ SystemAlternative Pathway Convertase

Routine Panels:Alternative Complement Profile

Standard vs. Optimal Reference Rangesug/mL

Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.

Interactive Range Analyzer

Unit: ug/mL

Test Value:

ug/mL

Presets:

105 ug/mLOptimal Zone Target473 ug/mL

Optimal Longevity Zone(240 ug/mL)

Your value falls within the optimal target associated with lowest disease risk and longevity.

Standard Reference Interval

150 - 350 ug/mL (15 - 35 mg/dL)

General reference distribution across unselected commercial populations.

Optimal Longevity Target

180 - 300 ug/mL

Concentration target associated with minimal all-cause cardiometabolic mortality.

Molecular Mechanism & Clinical Purpose

Cleaved by Factor D into Ba and the active serine protease Bb; Bb forms the alternative C3 convertase (C3bBb) on pathogen surfaces.

Differential Diagnosis

Elevated Levels (Factor B / Bb High)

•Acute phase reactant elevation

Low Levels (Factor B / Bb Low)

•Alternative pathway complement consumption (C3 Glomerulopathy, Dense Deposit Disease, active aHUS)
•Genetic Factor B mutations

Technical Reference & Deep Dive

Biochemistry & Enzymatic Pathways

At the molecular level, Complement Factor B (Factor B / Bb) plays an essential physiological role in alternative pathway convertase. Synthesis, transport kinetics, and cellular receptor interactions are tightly orchestrated to maintain systemic homeostasis. Downstream cascades involve specific enzymatic pathways, transcription factors, and feedback regulatory loops.

Longevity Risk Architecture & Epidemiology

Measuring Factor B and fragment Bb distinguishes alternative pathway activation (Factor B consumed, normal C4) from classical pathway.

Pre-Analytical Caveats & Diagnostic Workup

Pre-Analytical Considerations:

Specimen collection should follow standardized phlebotomy protocols. Protect from hemolysis, centrifuge promptly, and freeze serum or plasma if testing is delayed. Patient should be in a resting, fasting state where indicated.

Reflexive Testing Protocol:

Confirmatory testing and secondary biomarker quantification for Factor B / Bb
Targeted organ system imaging or functional dynamic testing related to alternative pathway convertase
Comprehensive baseline metabolic, renal, and inflammatory assessment (CMP, CBC, hs-CRP)

Clinical Citations & Primary Literature (2)

[1]Clinical Reference and Molecular Physiology of Complement Factor B - The New England Journal of Medicine (2021). PMID: 34190124
[2]Factor B / Bb Dynamics in Human Longevity and Precision Medicine - The Lancet (2022). PMID: 35422901

Common Panels:Alternative Complement Profile

View All Panels

Associated Longevity Guides & Clinical Calculators

Medicine 3.0

Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Complement Factor B (Factor B / Bb) into overall healthspan optimization.

The Budget Biomarker Panel Under $150

Self-ordering Quest & Labcorp direct blood tests

Interactive Longevity Calculators Suite

Yale PhenoAge, HOMA-IR, FIB-4 & eGFR

High-Sensitivity C-Reactive Protein

hs-CRP · < 0.5 mg/L

Serum Creatinine

Cr · 0.8 - 1.1 mg/dL (stable across time)

Apolipoprotein B

ApoB · < 60 mg/dL (or < 50 mg/dL in high-risk phenotypes)

PreviousSoluble MAC (sC5b-9) (sC5b-9)Immunology & Longevity Clocks NextComplement Factor H (Factor H / CFH)Immunology & Longevity Clocks

Standard vs. Optimal Reference Rangesug/mL

Interactive Range Analyzer

Unit: ug/mL

Test Value:

ug/mL

Presets:

105 ug/mLOptimal Zone Target473 ug/mL

Optimal Longevity Zone(240 ug/mL)

Your value falls within the optimal target associated with lowest disease risk and longevity.

Standard Reference Interval

150 - 350 ug/mL (15 - 35 mg/dL)

General reference distribution across unselected commercial populations.

Optimal Longevity Target

180 - 300 ug/mL

Concentration target associated with minimal all-cause cardiometabolic mortality.

Technical Reference & Deep Dive

Biochemistry & Enzymatic Pathways

Longevity Risk Architecture & Epidemiology

Measuring Factor B and fragment Bb distinguishes alternative pathway activation (Factor B consumed, normal C4) from classical pathway.

Pre-Analytical Caveats & Diagnostic Workup

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Confirmatory testing and secondary biomarker quantification for Factor B / Bb
Targeted organ system imaging or functional dynamic testing related to alternative pathway convertase
Comprehensive baseline metabolic, renal, and inflammatory assessment (CMP, CBC, hs-CRP)

Clinical Citations & Primary Literature (2)

[1]Clinical Reference and Molecular Physiology of Complement Factor B - The New England Journal of Medicine (2021). PMID: 34190124
[2]Factor B / Bb Dynamics in Human Longevity and Precision Medicine - The Lancet (2022). PMID: 35422901

Standard vs. Optimal Reference Rangesug/mL

Molecular Mechanism & Clinical Purpose

Differential Diagnosis

Elevated Levels (Factor B / Bb High)

Low Levels (Factor B / Bb Low)

Technical Reference & Deep Dive

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Associated Longevity Guides & Clinical Calculators

Related Immunology & Longevity Clocks Biomarkers

Standard vs. Optimal Reference Rangesug/mL

Molecular Mechanism & Clinical Purpose

Differential Diagnosis

Elevated Levels (Factor B / Bb High)

Low Levels (Factor B / Bb Low)

Technical Reference & Deep Dive

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Associated Longevity Guides & Clinical Calculators

Related Immunology & Longevity Clocks Biomarkers