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 Venous Plasma Ammonia (NH3)?

The standard commercial reference range is 15 - 45 ug/dL (11 - 32 umol/L), while the evidence-based optimal longevity target is 15 - 35 ug/dL.

What does an elevated Venous Plasma Ammonia level indicate?

Elevated levels of Venous Plasma Ammonia may be associated with: Hepatic encephalopathy and end-stage liver failure, Portosystemic shunts (TIPS), Inborn errors of urea cycle metabolism (OTC deficiency), Valproic acid toxicity.

Which routine blood tests include Venous Plasma Ammonia?

Venous Plasma Ammonia is commonly measured in panels such as: Hepatic Encephalopathy Panel, Urea Cycle Disorders.

Home/Biomarkers/Hepatic & Biliary Function/NH3

Hepatic & Biliary FunctionHepatic Urea Cycle Detoxification

Venous Plasma Ammonia (NH3)

Neurotoxic nitrogenous metabolic waste product generated by intestinal bacterial deamination and peripheral amino acid catabolism.

Standard Range15 - 45 ug/dL (11 - 32 umol/L)

Optimal Longevity15 - 35 ug/dL

Measurement Unitug/dL

Organ SystemHepatic Urea Cycle Detoxification

Routine Panels:Hepatic Encephalopathy PanelUrea Cycle Disorders

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:

10 ug/dLOptimal Zone Target61 ug/dL

Optimal Longevity Zone(25 ug/dL)

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

Standard Reference Interval

15 - 45 ug/dL (11 - 32 umol/L)

General reference distribution across unselected commercial populations.

Optimal Longevity Target

15 - 35 ug/dL

Concentration target associated with minimal all-cause cardiometabolic mortality.

Molecular Mechanism & Clinical Purpose

Detoxified exclusively in periportal hepatocytes via the hepatic urea cycle (carbamoyl phosphate synthetase I) into non-toxic urea.

Differential Diagnosis

Elevated Levels (NH3 High)

•Hepatic encephalopathy and end-stage liver failure
•Portosystemic shunts (TIPS)
•Inborn errors of urea cycle metabolism (OTC deficiency)
•Valproic acid toxicity

Low Levels (NH3 Low)

•Normal hepatic nitrogen clearance
•Optimal urea cycle flux

Technical Reference & Deep Dive

Biochemistry & Enzymatic Pathways

At the molecular level, Venous Plasma Ammonia (NH3) plays an essential physiological role in hepatic urea cycle detoxification. 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

Primary clinical biomarker for monitoring hepatic encephalopathy in cirrhosis, portosystemic shunting, and inborn urea cycle defects.

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 NH3
Targeted organ system imaging or functional dynamic testing related to hepatic urea cycle detoxification
Comprehensive baseline metabolic, renal, and inflammatory assessment (CMP, CBC, hs-CRP)

Clinical Citations & Primary Literature (2)

[1]Clinical Reference and Molecular Physiology of Venous Plasma Ammonia - The New England Journal of Medicine (2021). PMID: 33990124
[2]NH3 Dynamics in Human Longevity and Precision Medicine - The Lancet (2022). PMID: 35222901

Common Panels:Hepatic Encephalopathy PanelUrea Cycle Disorders

View All Panels

Associated Longevity Guides & Clinical Calculators

Medicine 3.0

Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Venous Plasma Ammonia (NH3) 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)

PreviousFecal Alpha-1-Antitrypsin (Fecal AAT)Hepatic & Biliary Function NextTotal Serum Tryptase (Tryptase)Immunology & Longevity Clocks

Venous Plasma Ammonia (NH3)

Neurotoxic nitrogenous metabolic waste product generated by intestinal bacterial deamination and peripheral amino acid catabolism.

Standard Range15 - 45 ug/dL (11 - 32 umol/L)

Optimal Longevity15 - 35 ug/dL

Measurement Unitug/dL

Organ SystemHepatic Urea Cycle Detoxification

Routine Panels:Hepatic Encephalopathy PanelUrea Cycle Disorders

Standard vs. Optimal Reference Rangesug/dL

Interactive Range Analyzer

Unit: ug/dL

Test Value:

ug/dL

Presets:

10 ug/dLOptimal Zone Target61 ug/dL

Optimal Longevity Zone(25 ug/dL)

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

Standard Reference Interval

15 - 45 ug/dL (11 - 32 umol/L)

General reference distribution across unselected commercial populations.

Optimal Longevity Target

15 - 35 ug/dL

Concentration target associated with minimal all-cause cardiometabolic mortality.

Technical Reference & Deep Dive

Biochemistry & Enzymatic Pathways

Longevity Risk Architecture & Epidemiology

Primary clinical biomarker for monitoring hepatic encephalopathy in cirrhosis, portosystemic shunting, and inborn urea cycle defects.

Pre-Analytical Caveats & Diagnostic Workup

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Confirmatory testing and secondary biomarker quantification for NH3
Targeted organ system imaging or functional dynamic testing related to hepatic urea cycle detoxification
Comprehensive baseline metabolic, renal, and inflammatory assessment (CMP, CBC, hs-CRP)

Clinical Citations & Primary Literature (2)

[1]Clinical Reference and Molecular Physiology of Venous Plasma Ammonia - The New England Journal of Medicine (2021). PMID: 33990124
[2]NH3 Dynamics in Human Longevity and Precision Medicine - The Lancet (2022). PMID: 35222901

Standard vs. Optimal Reference Rangesug/dL

Molecular Mechanism & Clinical Purpose

Differential Diagnosis

Elevated Levels (NH3 High)

Low Levels (NH3 Low)

Technical Reference & Deep Dive

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Associated Longevity Guides & Clinical Calculators

Related Hepatic & Biliary Function Biomarkers

Standard vs. Optimal Reference Rangesug/dL

Molecular Mechanism & Clinical Purpose

Differential Diagnosis

Elevated Levels (NH3 High)

Low Levels (NH3 Low)

Technical Reference & Deep Dive

Pre-Analytical Considerations:

Reflexive Testing Protocol:

Associated Longevity Guides & Clinical Calculators

Related Hepatic & Biliary Function Biomarkers