Potassium
Serum potassium is tightly regulated and drifts upward slightly with age, reflecting changes in kidney function, medications, and acid-base status in the population.
Unit: mmol/L · 12 groups · age and sex · 1 source
Filed under panels: Electrolyte Panel · topics: Metabolic , Renal , Electrolytes
Potassium by age and sex
| Age (years) | Males (mmol/L) | Females (mmol/L) |
|---|---|---|
| 20-29 | median 4.1 middle 90% 3.6 to 4.6 | median 4.1 middle 90% 3.6 to 4.5 |
| 30-39 | median 4.1 middle 90% 3.6 to 4.6 | median 4 middle 90% 3.5 to 4.6 |
| 40-49 | median 4.1 middle 90% 3.7 to 4.6 | median 4 middle 90% 3.5 to 4.5 |
| 50-59 | median 4.1 middle 90% 3.7 to 4.8 | median 4 middle 90% 3.5 to 4.6 |
| 60-69 | median 4.2 middle 90% 3.6 to 5 | median 4.1 middle 90% 3.5 to 4.6 |
| 70+ | median 4.3 middle 90% 3.6 to 5.1 | median 4.2 middle 90% 3.6 to 4.8 |
Download Potassium percentiles (CSV) Values at full stored precision; tables on this site may round for display. Licensed under CC BY 4.0.
Population Distribution
Serum potassium is the principal intracellular cation, with serum concentration kept within a narrow range by renal handling, aldosterone, acid-base status, and cellular shifts. It is part of the standard chemistry panel. These percentiles describe the full US adult population from NHANES 2017-March 2020 rather than a screened healthy subgroup.
Frequently Asked Questions
Why does potassium drift up with age?
Older adults more often have reduced kidney function, medications that retain potassium such as ACE inhibitors or ARBs, and shifts in acid-base status. That nudges the upper tail of the population distribution upward.
Why is potassium tightly regulated?
Serum potassium has a narrow window that is compatible with normal cardiac and neuromuscular function, so the kidney and cellular uptake work together to keep concentrations stable.
Does hemolysis affect this?
Yes, hemolyzed specimens can falsely elevate measured potassium. NHANES uses standardized collection protocols and quality controls. LabNorms does not exclude any samples for hemolysis, so these percentiles reflect results as NHANES reported them.
Data Sources
Cite this data
LabNorms. Potassium population percentiles by age and sex. Data: NHANES 2017-March 2020 Pre-Pandemic. https://labnorms.com/analytes/potassium/. Licensed under CC BY 4.0. Accessed [date].
Download Potassium percentiles (CSV) Values at full stored precision; tables on this site may round for display. Licensed under CC BY 4.0.