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BUN by age and sex

What’s typical for BUN at every adult age, from a U.S. government health survey of 19,127 people, next to the usual ranges labs print.

NHANES 2015–2016, 2017–March 2020 (pre-pandemic), August 2021–August 202319,127 adultsAI-verified against cited sources. Awaiting expert review

What’s typical at one age

Pick a sex and an age to see the spread among U.S. adults like that, and type a result to see where it falls.

U.S. women aged 40–49

1,529 people in NHANES, 2015–2016, 2017–March 2020 (pre-pandemic), August 2021–August 2023.

Women aged 40–49, 1,529 people: median 12, middle half 9.7 to 15, middle 90% 6.8 to 19 mg/dL. Usual range 6.0 to 21.

Median (half are lower)
12 mg/dL
Middle half of people
9.7 to 15
Middle 90% of people
6.8 to 19
Usual range a lab prints
6.0 to 21

Shaded: the middle 90% and middle half of people. Dark line: the median. The bracket above: the usual range.

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Across adult life

NHANES describes the US civilian, non-institutionalized population, not a 'healthy' reference group. People with disease, on medication, fasting or not (except fasting-subsample markers), smokers and so on are all included. A percentile says where a value sits among Americans of that sex and age, not whether it is normal.

How BUN varies with age in the U.S.Shaded: middle 90% and middle 50% of people. Line: the median. mg/dL. Point at any age, or focus the chart and use the arrow keys, to read both sexes in words.

Use the left and right arrow keys to read each age. Shift moves five years.

Reference data derived from CDC/NCHS National Health and Nutrition Examination Survey (NHANES), cycles 2015-2016, 2017-March 2020 (pre-pandemic), August 2021-August 2023. Analysis by bloodtesttracker.com; not endorsed by CDC, NCHS or HHS.

Every percentile

Download this table (CSV)

The 25th percentile means a quarter of people in that group had a lower result. In mg/dL. A dash means too few people were measured for the survey to publish that number.

Women

BUN percentiles for U.S. women by age, in mg/dL, NHANES 2015–2016, 2017–March 2020 (pre-pandemic), August 2021–August 2023
AgePeople2.5th5th10th25thMedian75th90th95th97.5th
18–291,68266791113151718
30–391,51467891114161819
40–491,529678101215171920
50–591,635789111316192123
60–691,9198910131518222529
70–791,0828911131620252831
80+585101113151923293335
All adults9,946678101316202226

Men

BUN percentiles for U.S. men by age, in mg/dL, NHANES 2015–2016, 2017–March 2020 (pre-pandemic), August 2021–August 2023
AgePeople2.5th5th10th25thMedian75th90th95th97.5th
18–291,640789111316192021
30–391,308789111316182022
40–491,3118910121517202123
50–591,4278910121518212425
60–691,80381011141619222527
70–791,12991012141721252933
80+563101213162025323845
All adults9,1817910121518212426

About these numbers

  • NHANES describes the US civilian, non-institutionalized population, not a 'healthy' reference group. People with disease, on medication, fasting or not (except fasting-subsample markers), smokers and so on are all included. A percentile says where a value sits among Americans of that sex and age, not whether it is normal.
  • Assays differ between labs and between NHANES cycles. Values from a commercial lab can sit a few percent higher or lower than NHANES for the same blood. Earlier cycles were bridged to the 2021-2023 method with NCHS equations where NCHS recommends it.
  • Age 80 and over is top-coded at 80 in public NHANES files, so the 80+ cell mixes everyone 80 and older.
  • 2021-2023 (cycle L) had a 25.7% exam response rate and no race/income oversampling; NCHS advises caution when combining it with earlier cycles.

Reference data derived from CDC/NCHS National Health and Nutrition Examination Survey (NHANES), cycles 2015-2016, 2017-March 2020 (pre-pandemic), August 2021-August 2023. Analysis by bloodtesttracker.com; not endorsed by CDC, NCHS or HHS.

Centers for Disease Control and Prevention (CDC). National Center for Health Statistics (NCHS). National Health and Nutrition Examination Survey Data. Hyattsville, MD: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, 2015-2016, 2017-March 2020 (pre-pandemic), August 2021-August 2023. https://wwwn.cdc.gov/nchs/nhanes/

How we use survey data

The usual range at every age

The reference range labs print, for each age group. Ranges differ a little between labs, so the range on your own report is the one your result is judged against.

Use the left and right arrow keys to step through the age groups. Every range is also in the table below.

Usual range of BUN by age, in mg/dL
WhoUsual range
Women, 18+6–21 mg/dL
Men, 18+8–24 mg/dL
1–177–20 mg/dL

Sources: Mayo Clinic Laboratories (test catalog copy hosted by Schneck Medical Center), Labcorp