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LIVER BIOMARKER

Albumin

Serum Albumin

The optimal range for Albumin (Serum Albumin) is commonly cited as 4.3–5.0 g/dL, tighter than the standard lab reference range of 3.5–5.0 g/dL. The main liver-synthesized serum protein - low levels signal liver dysfunction, malnutrition, or chronic disease.

STANDARD RANGE
3.5–5.0 g/dL
OPTIMAL (OPTIMIZATION)
4.3–5.0 g/dL
RANGE VISUALIZATION

How Albumin ranges relate

The standard lab range vs the optimization-focused target. Illustrative trajectory shows what a 12-week improvement pattern looks like — not real user data.

3.55STANDARD LAB RANGEOPTIMALWK 0WK 12ILLUSTRATIVE TRAJECTORY (NOT REAL DATA)
Standard lab rangeOptimization-focused targetIllustrative trajectory

What Albumin Measures

Albumin is the most abundant serum protein, synthesized exclusively by the liver. It is a cleaner long-term marker of liver synthetic function than ALT (half-life ~20 days vs minutes). Low values (<3.5) suggest chronic liver disease, malnutrition, nephrotic syndrome, or sustained inflammation.

Albumin is the primary carrier for hydrophobic molecules including calcium and many drugs - corrected calcium uses albumin.

What Affects This Biomarker

Albumin is influenced by: liver synthetic capacity (chronic disease lowers), protein intake, inflammation (negative acute phase reactant - falls during illness), nephrotic syndrome (urinary loss), and volume status (hemodilution in overload).

In the Context of Peptide Protocols

Reviewed as part of standard CMP. Persistent values below 4.0 warrant follow-up - could be diet, inflammation, or early liver synthetic dysfunction. Longevity cohorts show higher albumin associated with lower all-cause mortality.

Frequently Asked Questions

What does Albumin measure?

Albumin is the most abundant serum protein, synthesized exclusively by the liver. It is a cleaner long-term marker of liver synthetic function than ALT (half-life ~20 days vs minutes). Low values (<3.5) suggest chronic liver disease, malnutrition, nephrotic syndrome, or sustained inflammation.

What is the optimal range for Albumin?

The optimal range for Albumin is commonly cited as 4.3–5.0 g/dL. The standard lab reference range is 3.5–5.0 g/dL.

What affects Albumin levels?

Albumin is influenced by: liver synthetic capacity (chronic disease lowers), protein intake, inflammation (negative acute phase reactant - falls during illness), nephrotic syndrome (urinary loss), and volume status (hemodilution in overload).

Where This Fits in Your Panel

Albumin is one marker on a fuller panel. The Peptide Blood Work Checklist lays out the complete baseline panel, what to add by protocol type, and when to retest.

See the full blood work checklist →
Track Albumin over time.

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Last reviewed: June 2026

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