Which tests measure Ascorbic Acid (Vitamin C)?

Ascorbic Acid (Vitamin C) is measured in 1 test on BiomarkersLabs.com, including Vitamin C (Ascorbic Acid) Test.

Biomarker Reference · Vit C

What does the Ascorbic Acid (Vitamin C) test measure?

Q: What is the reference range for Ascorbic Acid (Vitamin C)?

The standard reference range for Ascorbic Acid (Vitamin C) is 0.4–2.0 mg/dL (23–114 µmol/L). Reference ranges vary by laboratory and assay platform — interpret in context of the issuing laboratory's stated range.

Ascorbic Acid (Vitamin C) (Vit C) is a clinical biomarker used in vitamins-minerals assessment. Ascorbic acid is a water-soluble antioxidant vitamin that humans cannot synthesise endogenously due to the absence of the enzyme L-gulonolactone oxidase. It is measured in 1 laboratory test on BiomarkersLabs.com.

Reference Range: 0.4–2.0 mg/dL (23–114 µmol/L)
Units: mg/dL, µmol/L
Measured In: 1 test
Category: Vitamins & Minerals

Functional medicine optimal0.6–1.6 mg/dL (34–91 µmol/L) — functional medicine optimal range; some integrative protocols target 1.0–1.4 mg/dL # REVIEWER FLAG: Optimal range thresholds are not standardised across guidelines — functional medicine consensus varies. Reviewer to confirm against IFM or equivalent source.

What is Ascorbic Acid (Vitamin C)?

Ascorbic acid is a water-soluble antioxidant vitamin that humans cannot synthesise endogenously due to the absence of the enzyme L-gulonolactone oxidase. It is absorbed in the small intestine via sodium-dependent vitamin C transporters (SVCT1/SVCT2) and circulates primarily in plasma, with tissue concentrations substantially higher than plasma — particularly in the adrenal glands, leucocytes, and brain. Plasma half-life is approximately 10–20 days at physiological concentrations. The vitamin participates in collagen hydroxylation, catecholamine synthesis, iron absorption enhancement, and broad antioxidant defence.

Why is Ascorbic Acid (Vitamin C) measured?

Plasma ascorbic acid levels directly reflect recent dietary intake and absorption status, making them the preferred marker for assessing vitamin C deficiency and adequacy. Levels below 0.2 mg/dL are associated with clinical scurvy, while subclinical deficiency (0.2–0.4 mg/dL) correlates with impaired collagen synthesis, immune compromise, and increased oxidative stress burden. Practitioners use this test to guide supplementation, monitor repletion, and investigate unexplained fatigue, poor wound healing, or inflammatory states where antioxidant depletion is suspected.

Reference ranges

Standard reference: 0.4–2.0 mg/dL (23–114 µmol/L)
Functional medicine optimal: 0.6–1.6 mg/dL (34–91 µmol/L) — functional medicine optimal range; some integrative protocols target 1.0–1.4 mg/dL # REVIEWER FLAG: Optimal range thresholds are not standardised across guidelines — functional medicine consensus varies. Reviewer to confirm against IFM or equivalent source.
Units: mg/dL, µmol/L

Reference ranges vary by laboratory and assay platform. Interpret in context of the issuing laboratory's stated range.

Tests that measure Ascorbic Acid (Vitamin C)

1 test on BiomarkersLabs.com include this biomarker.

BML-VIT-001Comprehensive

Vitamin C (Ascorbic Acid) Test

Ascorbic Acid (Vitamin C) reference range in this test: 0.4–2.0 mg/dL (23–114 µmol/L)

Related clinical conditions

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