Vitamin C
Vitamin C is a water-soluble vitamin whose serum concentration tracks recent intake. Across US males aged 30-39, the median serum vitamin C in NHANES 2017-2018 is 0.85 mg/dL.
Unit: mg/dL · 12 groups · age and sex · 1 source
Vitamin C by age and sex
| Age (years) | Males (mg/dL) | Females (mg/dL) |
|---|---|---|
| 20-29 | median 0.73 middle 90% 0.16 to 1.33 | median 0.97 middle 90% 0.20 to 1.63 |
| 30-39 | median 0.85 middle 90% 0.18 to 1.39 | median 0.94 middle 90% 0.18 to 1.56 |
| 40-49 | median 0.75 middle 90% 0.15 to 1.32 | median 0.95 middle 90% 0.18 to 1.68 |
| 50-59 | median 0.87 middle 90% 0.17 to 1.72 | median 0.97 middle 90% 0.16 to 1.97 |
| 60-69 | median 0.77 middle 90% 0.15 to 1.47 | median 1.08 middle 90% 0.17 to 2.06 |
| 70+ | median 0.99 middle 90% 0.16 to 1.82 | median 1.15 middle 90% 0.18 to 2.15 |
Download Vitamin C percentiles (CSV) Values at full stored precision; tables on this site may round for display. Licensed under CC BY 4.0.
Population Distribution
Serum vitamin C (ascorbic acid) is the standard population marker of vitamin C status. Unlike fat-soluble vitamins, the body does not store vitamin C in large amounts, so serum levels respond to recent dietary intake on a timescale of hours to days. Smoking status is one contributor to variation in serum vitamin C for a given intake. NHANES publishes vitamin C in mg/dL; LabNorms displays it in mg/dL and exposes µmol/L via the unit toggle.
Frequently Asked Questions
Why does serum vitamin C respond so quickly to intake?
Vitamin C is water-soluble and not stored in significant amounts. Serum levels can change within hours of intake, so the measure reflects recent dietary or supplement consumption rather than longer-term status.
Why is the population distribution of vitamin C so wide?
Plasma vitamin C is shaped by recent dietary intake (especially fruits and vegetables), supplement use, and smoking status. Each of these varies considerably across the population, producing a wide distribution.
Why are these population percentiles, not clinical reference intervals?
LabNorms shows where a given value sits in the US adult population distribution. Clinical reference intervals are produced by laboratories using their own measurement protocols and answer a different question. Both can be useful, but they are not interchangeable.
Data Sources
Cite this data
LabNorms. Vitamin C population percentiles by age and sex. Data: NHANES 2017-2018. https://labnorms.com/analytes/vitamin-c/. Licensed under CC BY 4.0. Accessed [date].
Download Vitamin C percentiles (CSV) Values at full stored precision; tables on this site may round for display. Licensed under CC BY 4.0.