Urea
Urea is a waste product of protein breakdown that the kidneys excrete. Its level depends on the kidneys, but also on hydration and protein intake — so it is less specific than creatinine.
| Rating | Range | What it means |
|---|---|---|
| Talk to a doctor | below 2.8 mmol/L | Low urea — interpret in context (diet/liver). |
| Good | 2.8 – 7.5 mmol/L | Within the reference range. |
| Talk to a doctor | 7.5 mmol/L and above | Elevated — kidneys/dehydration; seek advice. |
This marker also has 5 age- or sex-specific range sets in the app — the table shows the general one.
Why it matters
An elevated level can be a sign of kidney issues or dehydration; it is not a KDIGO staging marker — use the reference interval.
If it’s low
Low urea is mostly insignificant; it accompanies a low-protein diet, liver disease or pregnancy.
If it’s high
High urea can indicate dehydration, a lot of protein in the diet or reduced kidney function; a high ratio to creatinine often means dehydration or gastrointestinal bleeding.
What to do
Interpret it with kidney function and hydration. For assessing the kidneys, eGFR is more reliable; urea adds context (hydration).
Read together with
Creatinine · eGFR
Part of the guide: Kidneys & electrolytes →
Articles about this marker
- Blood chemistry tests: normal values for ALT, AST, GGT, CRP, CK, creatinine and glucoseReading your report
- High BUN or urea: what it means, with creatinine and the BUN/creatinine ratioMarker explained
- Kidneys: eGFR and creatinine — what they mean and how to protect themMarker explained
This content is for information only and is not a substitute for medical advice. Talk to your doctor about your results.
Your number, not the average
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