LabNorms Population Percentiles

NHANES 2017-2018

National Health and Nutrition Examination Survey 2017-2018 Cycle (J) (2017–2018)

NHANES 2017-2018 overview: https://wwwn.cdc.gov/nchs/nhanes/continuousnhanes/overview.aspx?Cycle=2017-2018

Vitamin D codebook (VID_J): https://wwwn.cdc.gov/Nchs/Data/Nhanes/Public/2017/DataFiles/VID_J.htm

Vitamins A, E, and Carotenoids codebook (VITAEC_J): https://wwwn.cdc.gov/Nchs/Data/Nhanes/Public/2017/DataFiles/VITAEC_J.htm

Vitamin C codebook (VIC_J): https://wwwn.cdc.gov/Nchs/Data/Nhanes/Public/2017/DataFiles/VIC_J.htm

Demographics codebook (DEMO_J): https://wwwn.cdc.gov/Nchs/Data/Nhanes/Public/2017/DataFiles/DEMO_J.htm

Population

US civilian non-institutionalized population, all ages

Study Type

Cross-sectional nationally representative survey

About This Dataset

Some vitamin assays are not published as combined 2017-March 2020 pre-pandemic files. For 25-hydroxyvitamin D, vitamin A (retinol), vitamin E (alpha-tocopherol), and vitamin C, LabNorms uses the NHANES 2017-2018 cycle alone (J-cycle files) with the cycle's published two-year MEC weight WTMEC2YR applied directly. These percentiles should not be treated as two-cycle pooled estimates; effective sample size is smaller and tail precision is correspondingly reduced compared with analytes pooled across cycles.

Limitations

  • US population only (distributions may differ in other countries)
  • Cross-sectional design cannot establish causal relationships
  • Single-cycle estimates have wider effective tails than pooled-cycle estimates used for other LabNorms analytes
  • Self-reported supplement use is not used to exclude participants because NHANES does not capture supplementation reliably enough for consistent exclusion
  • 25-hydroxyvitamin D is the LC-MS/MS sum of D2 and D3, excluding the C3-epi-25(OH)D3 isomer

Used for

Panels

Demographic Slices