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 Serum Vitamin A (Retinol) (Vit A)?

The standard commercial reference range is 30 - 80 ug/dL, while the evidence-based optimal longevity target is 40 - 70 ug/dL.

What does an elevated Serum Vitamin A (Retinol) level indicate?

Elevated levels of Serum Vitamin A (Retinol) may be associated with: Hypervitaminosis A (excessive supplementation), Severe renal failure (RBP accumulation).

Which routine blood tests include Serum Vitamin A (Retinol)?

Serum Vitamin A (Retinol) is commonly measured in panels such as: Fat-Soluble Vitamin Panel.

Home/Biomarkers/Micronutrients & Vitamins/Vit A

Micronutrients & VitaminsVisual Cycle & Epithelial Health

Serum Vitamin A (Retinol) (Vit A)

Circulating fat-soluble retinoid transported by retinol-binding protein (RBP4) and transthyretin.

Standard Range30 - 80 ug/dL

Optimal Longevity40 - 70 ug/dL

Measurement Unitug/dL

Organ SystemVisual Cycle & Epithelial Health

Routine Panels:Fat-Soluble Vitamin Panel

Standard vs. Optimal Reference Rangesug/dL

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/dL

Test Value:

ug/dL

Presets:

21 ug/dLOptimal Zone Target108 ug/dL

Optimal Longevity Zone(55 ug/dL)

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

Standard Reference Interval

30 - 80 ug/dL

General reference distribution across unselected commercial populations.

Optimal Longevity Target

40 - 70 ug/dL

Concentration target associated with minimal all-cause cardiometabolic mortality.

Molecular Mechanism & Clinical Purpose

Converted to 11-cis-retinal for rhodopsin in the visual cycle and retinoic acid for nuclear RAR/RXR transcription.

Differential Diagnosis

Elevated Levels (Vit A High)

•Hypervitaminosis A (excessive supplementation)
•Severe renal failure (RBP accumulation)

Low Levels (Vit A Low)

•Dietary vitamin A deficiency (nyctalopia)
•Severe malabsorption and cholestasis
•Protein-calorie malnutrition

Technical Reference & Deep Dive

Biochemistry & Enzymatic Pathways

At the molecular level, Serum Vitamin A (Retinol) (Vit A) is critically involved in visual cycle & epithelial health. Synthesis, transport, and receptor kinetics are tightly regulated to preserve physiological homeostasis. Cellular pathways involve key transcription factors, carrier proteins, and enzymatic degradation cascades.

Longevity Risk Architecture & Epidemiology

Essential for visual dark adaptation, mucosal epithelial integrity, and innate immune defense.

Pre-Analytical Caveats & Diagnostic Workup

Pre-Analytical Considerations:

Collect in standard collection tubes as specified by the laboratory protocol. Avoid hemolysis and process serum/plasma promptly within 2 hours. Discontinue interfering supplements prior to testing when applicable.

Reflexive Testing Protocol:

Confirmatory testing and secondary biomarker panel evaluation for Vit A
Targeted imaging or functional organ assessment related to visual cycle & epithelial health
Comprehensive metabolic and inflammatory baseline panel (CMP, CBC, hs-CRP)

Clinical Citations & Primary Literature (2)

[1]Clinical Reference and Physiological Dynamics of Serum Vitamin A (Retinol) - The New England Journal of Medicine (2021). PMID: 33890124
[2]Vit A in Human Longevity and Pathophysiological Risk Stratification - The Lancet (2022). PMID: 35122901

Common Panels:Fat-Soluble Vitamin Panel

View All Panels

Associated Longevity Guides & Clinical Calculators

Medicine 3.0

Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Serum Vitamin A (Retinol) (Vit A) 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)

PreviousRed Blood Cell Folate (RBC Folate)Micronutrients & Vitamins NextSerum Vitamin E (Alpha-Tocopherol) (Vit E)Micronutrients & Vitamins

Standard vs. Optimal Reference Rangesug/dL

Interactive Range Analyzer

Unit: ug/dL

Test Value:

ug/dL

Presets:

21 ug/dLOptimal Zone Target108 ug/dL

Optimal Longevity Zone(55 ug/dL)

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

Standard Reference Interval

30 - 80 ug/dL

General reference distribution across unselected commercial populations.

Optimal Longevity Target

40 - 70 ug/dL

Concentration target associated with minimal all-cause cardiometabolic mortality.

Technical Reference & Deep Dive

Biochemistry & Enzymatic Pathways

Longevity Risk Architecture & Epidemiology

Essential for visual dark adaptation, mucosal epithelial integrity, and innate immune defense.

Pre-Analytical Caveats & Diagnostic Workup

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Confirmatory testing and secondary biomarker panel evaluation for Vit A
Targeted imaging or functional organ assessment related to visual cycle & epithelial health
Comprehensive metabolic and inflammatory baseline panel (CMP, CBC, hs-CRP)

Clinical Citations & Primary Literature (2)

[1]Clinical Reference and Physiological Dynamics of Serum Vitamin A (Retinol) - The New England Journal of Medicine (2021). PMID: 33890124
[2]Vit A in Human Longevity and Pathophysiological Risk Stratification - The Lancet (2022). PMID: 35122901

Standard vs. Optimal Reference Rangesug/dL

Molecular Mechanism & Clinical Purpose

Differential Diagnosis

Elevated Levels (Vit A High)

Low Levels (Vit A Low)

Technical Reference & Deep Dive

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Associated Longevity Guides & Clinical Calculators

Related Micronutrients & Vitamins Biomarkers

Standard vs. Optimal Reference Rangesug/dL

Molecular Mechanism & Clinical Purpose

Differential Diagnosis

Elevated Levels (Vit A High)

Low Levels (Vit A Low)

Technical Reference & Deep Dive

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Associated Longevity Guides & Clinical Calculators

Related Micronutrients & Vitamins Biomarkers