Serum creatinine
Creatinine is a breakdown product of muscle that the kidneys filter out. A US survey laboratory lists 0.67 to 1.17 mg/dL for men and 0.51 to 0.95 for women, and an earlier manual lists wider ranges. More muscle, creatine supplements and a cooked meat meal each raise the result. Cohorts link high and very low levels to worse outcomes.
- Status
- Part of routine basic and comprehensive metabolic blood panels, ordered by a clinician and also sold direct to consumers by some US laboratories. FDA classifies creatinine test systems as class II devices [1]. A kidney filtration estimate calculated from it, eGFR, has its own page.
- Measures
- The concentration of creatinine in serum. Creatinine is a breakdown product of creatine phosphate from muscle, and the kidneys remove it by filtration [2].
- Also called
- creatinine, serum creatinine, creatinine serum, plasma creatinine, creat, crea, SCr, sCr, Cr, creatinine blood test
- Tested for
- kidney function, kidney disease screening, acute kidney injury, medication dosing, kidney check while taking creatine, checkups on blood pressure or diabetes medication
Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on
Linked in research4
- LimitedLimited evidence: one British cohort of 7,690 middle-aged men linked creatinine above 1.31 mg/dL to 60% more strokes over about 15 years.
- LimitedLimited evidence: in one hospital cohort a rise in creatinine of 0.5 mg/dL or more during the stay went with 6.5 times the odds of death.
- LimitedLimited evidence: one Japanese cohort of 8,570 men linked creatinine of 0.40 to 0.60 mg/dL to about twice the odds of type 2 diabetes over 4 years.
- LimitedLimited evidence: one cohort of 11,291 intensive care patients linked a baseline creatinine of 0.6 mg/dL or below to about 2.6 times the odds of death.
Reported risks0
No risks sourced yet.
Reference ranges
Each range is the one its source published, in mg/dL. Also reported in µmol/L. Where sources differ, each is shown.
US national survey laboratory procedure manual, 2017 to 2018, men
Adult men, as the reference range printed for the serum assay · [2]
| Range | What the source calls it |
|---|---|
| below 0.67 mg/dL | No name given |
| 0.67 to 1.17 mg/dL | "reference range" |
| above 1.17 mg/dL | No name given |
The reference range listed in the laboratory manual for the method used in the 2017 to 2018 US National Health and Nutrition Examination Survey (Roche Cobas 6000, enzymatic method), with no account of how it was derived and no age bands. The manual states that the enzymatic method agrees well with reference chromatography methods and is less open to interference than picric acid methods [2].
US national survey laboratory procedure manual, 2017 to 2018, women
Adult women, as the reference range printed for the serum assay · [2]
| Range | What the source calls it |
|---|---|
| below 0.51 mg/dL | No name given |
| 0.51 to 0.95 mg/dL | "reference range" |
| above 0.95 mg/dL | No name given |
From the same manual, with no account of how it was derived [2].
US national survey laboratory procedure manual, 2015 to 2016, males older than 15
Males older than 15, as the reference range printed for the assay · [3]
| Range | What the source calls it |
|---|---|
| below 0.7 mg/dL | No name given |
| 0.7 to 1.3 mg/dL | "reference range" |
| above 1.3 mg/dL | No name given |
From the manual for the method used in the 2015 to 2016 survey (Beckman UniCel DxC 800, kinetic alkaline picrate method, run by Collaborative Laboratory Services). The manual states that its reference ranges were established from wellness participants with an age mix similar to the laboratory's patients. Two assays used by the same national survey print different ranges, and the upper limit here is 0.13 mg/dL above the one for the 2017 to 2018 assay. The laboratory telephones results above 6.0 mg/dL for its own patients, and reported survey results above 1.7 mg/dL early [3][2].
US national survey laboratory procedure manual, 2015 to 2016, females older than 15
Females older than 15, as the reference range printed for the assay · [3]
| Range | What the source calls it |
|---|---|
| below 0.6 mg/dL | No name given |
| 0.6 to 1.1 mg/dL | "reference range" |
| above 1.1 mg/dL | No name given |
From the same manual, established the same way. The upper limit is 0.15 mg/dL above the one for the 2017 to 2018 assay [3][2].
US national survey laboratory procedure manual, 2015 to 2016, children aged 1 to 15
Children aged 1 to 15, boys and girls together · [3]
| Range | What the source calls it |
|---|---|
| below 0.3 mg/dL | No name given |
| 0.3 to 1 mg/dL | "reference range" |
| above 1 mg/dL | No name given |
The manual attributes its pediatric ranges to a 1995 multicenter guideline for the analyzer, built on data from Montreal, Miami and Denver. One range covers ages 1 to 15, across which muscle mass changes greatly. The manual prints the age bands as 1 to 15 and older than 15 without saying which band a child of exactly 15 falls in [3].
US national survey laboratory procedure manual, 2015 to 2016, infants aged 1 month to 1 year
Infants aged 1 month to 1 year · [3]
| Range | What the source calls it |
|---|---|
| below 0.3 mg/dL | No name given |
| 0.3 to 0.6 mg/dL | "reference range" |
| above 0.6 mg/dL | No name given |
From the same manual and the same 1995 pediatric guideline for the analyzer [3].
US national survey laboratory procedure manual, 2015 to 2016, newborns under 1 month
Newborns from birth to 1 month · [3]
| Range | What the source calls it |
|---|---|
| below 0.3 mg/dL | No name given |
| 0.3 to 0.8 mg/dL | "reference range" |
| above 0.8 mg/dL | No name given |
From the same manual and the same 1995 pediatric guideline for the analyzer [3].
Wiles and colleagues, systematic review of creatinine in pregnancy, 2019
Pregnant women in any trimester · [4]
| Range | What the source calls it |
|---|---|
| 0.87 or below mg/dL | No name given |
| above 0.87 mg/dL | "outside the normal range for pregnancy" |
From a systematic review of 49 studies with 4,421 creatinine values in pregnancy. Mean creatinine in pregnancy was 84%, 77% and 80% of the nonpregnant mean in the first, second and third trimesters, and the upper limit was 85%, 80% and 86% of the nonpregnant upper limit. The authors applied this to a nonpregnant interval of 0.51 to 1.02 mg/dL and propose one threshold for all of pregnancy, printed as above 77 µmol/L (0.87 mg/dL). The studies pooled used several assay methods. No lower limit is given, so this block does not classify low results [4].
Kidney Disease: Improving Global Outcomes (KDIGO) acute kidney injury guideline, 2012, stage 3 criterion
People who already meet the guideline's definition of acute kidney injury · [5]
| Range | What the source calls it |
|---|---|
| below 4 mg/dL | No name given |
| 4 or above mg/dL | "Stage 3" A doctor, immediately |
The guideline defines acute kidney injury by change, not by one level: a rise of 0.3 mg/dL or more within 48 hours, a rise to 1.5 times baseline or more within 7 days, or low urine output. Those are changes over time, a different quantity from a single result, and they are not placed here. It then stages severity, and a person who has met the definition is automatically in stage 3, its highest stage, on reaching 4.0 mg/dL. A result of 4.0 mg/dL without that prior rise is not stage 3 under the guideline. Stages 1 and 2 are defined by rises from a person's own baseline. The guideline notes that small children may not be able to reach 4.0 mg/dL. Its conversion table multiplies mg/dL by 88.4 to give µmol/L [5].
What has been shown to move it
Shown to lower it1
Kidney function
Shown to lower serum creatinine and urine protein when added to treatment in chronic kidney disease, in low-quality trials.
The numbers and sources
- Effect
- In a Cochrane review of 22 studies (1,746 participants), Cordyceps preparations added to conventional treatment lowered serum creatinine by 60.76 µmol/L (14 studies), raised creatinine clearance by 9.22 mL/min (6 studies) and cut 24-hour proteinuria by 0.15 g (4 studies) in people not on dialysis [6]. A 2025 meta-analysis of 15 studies (1,310 patients) with kidney dysfunction, including acute kidney injury, found Cordyceps sinensis as an add-on lowered blood creatinine, shortened the period of low urine output and raised urine osmolality [7].
- Population
- People with chronic kidney disease [6]; people with kidney dysfunction, including acute kidney injury [7].
- Sources
- [6], [7]
- Caveats
- Both reviews rest on low-quality trials. Risk of bias was high in 4 studies and unclear in 18, and the Cochrane authors could not reach definitive conclusions [6]. The 2025 review reported overall efficacy as diagnostic accuracy statistics, gives no size for the creatinine change in its abstract, and found results differed between northern and southern Chinese patients [7].
Shown to raise it9
Raised serum creatinine and kidney markers
Shown to raise blood creatinine, which lowers kidney estimates based on it. Kidney function measured another way did not change.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- In 26 RCTs (1,036 participants), serum creatinine rose 0.14 mg/dL (95% CI 0.05 to 0.22, I² 93.9%) and creatinine-based GFR estimates fell 10.75 mL/min (95% CI -17.48 to -4.02). GFR measured with Cr-EDTA, which does not rely on creatinine, did not differ (5.89 mL/min, 95% CI -0.30 to 12.08), nor did urea, albuminuria or proteinuria [18]. In 20 randomized trials, serum creatinine rose 0.13 mg/dL (95% CI 0.07 to 0.18), and urea and eGFR did not differ (eGFR -5.20 mL/min/1.73 m², 95% CI -15.00 to 4.60) [19]. In 12 studies (440 participants), serum creatinine rose by a mean of 0.07 (95% CI 0.01 to 0.12), significant at 1 week or less and after 12 weeks but not at 1 to 12 weeks. Glomerular filtration rate did not differ from control [20].
- Population
- Healthy people and people with chronic kidney disease, including a hemodialysis subgroup [18]; 19 RCTs and one crossover trial [19]; mostly healthy adults, 177 on creatine and 263 controls in the creatinine analysis [20].
- Sources
- [18], [19], [20]
- Caveats
- Creatinine is a breakdown product of creatine, so a higher reading and a lower creatinine-based GFR estimate can occur without a change in filtration. The authors of [18] attribute the changes to altered creatinine metabolism, since Cr-EDTA GFR did not change. The 2025 abstract reports its creatinine difference in µmol/L, a unit at which 0.07 would be negligible, and the unit may be a reporting error [20]. The authors of [19] call for trials longer than 1 year.
Kidney function changes
Shown to raise creatinine in some people, with kidney dysfunction in 2.4% on lisinopril against 1.1% of controls after a heart attack.
The numbers and sources
- How common
- Common: between 1 in 100 and 1 in 10 people.
- Effect
- Minor, reversible rises in blood urea nitrogen and creatinine occurred in about 2% of people with hypertension on lisinopril alone and in 11.6% of people with heart failure also taking a diuretic. In GISSI-3, kidney dysfunction, defined as creatinine above 3 mg/dL or doubled, occurred in 2.4% on lisinopril and 1.1% of those not given it. In ATLAS, raised creatinine was reported in 10% on the high dose and 7% on the low dose. The label warns that acute kidney failure can occur, particularly with renal artery stenosis, chronic kidney disease, severe heart failure or volume depletion [3].
- Population
- People in lisinopril clinical trials, including 19,394 in GISSI-3 and 3,164 in ATLAS [3].
- Sources
- [3]
- Caveats
- Rises were more frequent with diuretics and often resolved when the diuretic dose was lowered [3]. For the long-term effect on kidney disease, see the kidney outcome block above.
Kidney function changes
Shown to raise creatinine in some people with heart failure, by more than half in 3.9% on valsartan against 0.9% on placebo.
The numbers and sources
- How common
- Common: between 1 in 100 and 1 in 10 people.
- Effect
- In heart failure trials, creatinine rose by more than 50% in 3.9% on valsartan and 0.9% on placebo. After a heart attack, creatinine doubled in 4.2% on valsartan and 3.4% on captopril [14]. The losartan label warns that acute kidney failure can occur, particularly with renal artery stenosis, chronic kidney disease, severe heart failure or volume depletion [10].
- Population
- People in valsartan heart failure and heart attack trials [14].
- Sources
- [14], [10]
- Caveats
- For the long-term effect on diabetic kidney disease, see the kidney outcome block above.
Kidney function after zoledronic acid
The label warns zoledronic acid can impair kidney function, with a short-lived creatinine rise within 10 days in 1.8% against 0.8% on placebo.
The numbers and sources
- How common
- Common: between 1 in 100 and 1 in 10 people.
- Effect
- A transient rise in serum creatinine within 10 days of dosing occurred in 1.8% on zoledronic acid and 0.8% on placebo and resolved without treatment. Changes in creatinine clearance over 3 years and rates of kidney failure were comparable to placebo. The label reports rare acute kidney failure and contraindicates it below a creatinine clearance of 35 mL/min [13].
- Population
- Women in the main osteoporosis trial, which excluded creatinine clearance under 30 mL/min [13].
- Sources
- [13]
- Caveats
- People with poorer kidney function were excluded from the trial.
Fenofibrate: raised creatinine
Shown to raise serum creatinine about twice as often as placebo across fibrate trials. The label says the rise tends to reverse after stopping.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- Increases in serum creatinine were common on fibrates (RR 1.99, 95% CI 1.46 to 2.70) [9]. The fenofibrate label reports creatinine rises that tend to return to baseline after stopping, with unknown clinical significance [7].
- Population
- Fibrate trials [9]; label statement [7].
- Sources
- [9], [7]
- Caveats
- A creatinine rise on fenofibrate may not reflect a fall in kidney filtration, and protein in the urine fell in trials.
Early drop in kidney filtration and acute kidney injury
Mixed results: the labels report a small drop in eGFR in the first weeks and kidney injury reports after marketing, while pooled trials found 23% fewer acute kidney injuries.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- The empagliflozin label states that starting treatment raises serum creatinine and lowers eGFR within weeks, then stabilizes. In its cardiovascular trial the change generally did not exceed 0.1 mg/dL and 9.0 mL/min/1.73 m² at week 4, and reversed after stopping. Acute kidney injury is listed among postmarketing reports [20]. Across 13 placebo-controlled trials, allocation to an SGLT2 inhibitor lowered the risk of acute kidney injury by 23% (RR 0.77, 95% CI 0.70 to 0.84) [4]. In the dapagliflozin heart failure trial, kidney adverse events did not differ from placebo [2].
- Population
- Adults in empagliflozin trials [20]; 90,409 participants in 13 trials [4]; 4,744 adults with heart failure [2].
- Sources
- [20], [4], [2]
- Caveats
- The label gives no share of people for the early eGFR drop. Postmarketing reports have no denominator.
Kidney function and low blood pressure
Shown to raise creatinine in heart failure. The label warns of dehydration, low blood pressure and worsening kidney function from excess fluid loss.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- In heart failure with preserved ejection fraction, spironolactone was associated with increased serum creatinine. With frequent monitoring, creatinine of 3.0 mg/dL or higher and dialysis did not differ significantly from placebo [4]. The label states that excessive diuresis may cause symptomatic dehydration, low blood pressure and worsening kidney function, particularly in salt-depleted people or those taking ACE inhibitors or ARBs, and that it can also cause low sodium, low magnesium, low calcium, raised blood sugar and raised uric acid [3].
- Population
- 3,445 people with heart failure [4].
- Sources
- [4], [3]
- Caveats
- The abstract gives no rate for the creatinine rise.
Kidney function
Linked to small rises in creatinine and urea, with raised creatinine in 7.4% of bumetanide patients tested. High furosemide doses caused transient worsening of kidney function in one trial.
The numbers and sources
- How common
- Common: between 1 in 100 and 1 in 10 people.
- Effect
- Torsemide 10 mg a day for 6 weeks raised blood urea nitrogen a mean 1.8 mg/dL and creatinine 0.05 mg/dL, reversing after stopping [1]. Raised creatinine was reported in 7.4% and raised urea (azotemia) in 10.6% of patients tested on bumetanide [15]. In acute heart failure, the high-dose furosemide strategy brought transient worsening of kidney function [2].
- Population
- Hypertensive patients [1]; bumetanide-treated patients [15]; 308 patients [2].
- Sources
- [1], [15], [2]
- Caveats
- Creatinine changes during fluid removal can reflect less blood volume rather than kidney damage. No placebo group for the bumetanide figures.
Kidney function changes
Limited evidence: creatinine rises were more frequent on thiazides than placebo in two trials, and kidney injury was more frequent on chlorthalidone than hydrochlorothiazide in one cohort.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- A creatinine level above 150% of baseline was more frequent on hydrochlorothiazide than placebo in the kidney stone trial [13], and reversible creatinine rises were more frequent on chlorthalidone than placebo in advanced kidney disease [3]. In a cohort of first-time users, acute kidney failure (HR 1.37, 95% CI 1.15 to 1.63) and chronic kidney disease (HR 1.24, 95% CI 1.09 to 1.42) were more frequent on chlorthalidone than hydrochlorothiazide [8].
- Population
- 416 people with recurrent kidney stones [13]; 160 people with stage 4 chronic kidney disease [3]; 730,225 first-time users [8].
- Sources
- [13], [3], [8]
- Caveats
- None of the abstracts gives the rates.
Tested, and not shown to change it2
Kidney function in people without kidney disease
Shown to raise kidney filtration rate, urea and urine calcium in people without kidney disease, with no consistent sign of kidney injury in mostly short trials.
In 22 RCTs, eGFR rose (SMD 0.39, 95% CI 0.09 to 0.69, I² 74.9%) and serum creatinine did not change (SMD 0.08, 95% CI -0.09 to 0.25).
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- Across 30 studies (2,160 people), GFR rose 7.18 mL/min/1.73 m² more on high-protein diets (95% CI 4.45 to 9.91), with higher serum urea (1.75 mmol/L), urinary calcium (25.43 mg a day) and serum uric acid [11]. In 22 RCTs, eGFR rose (SMD 0.39, 95% CI 0.09 to 0.69, I² 74.9%) and serum creatinine did not change (SMD 0.08, 95% CI -0.09 to 0.25) [5]. In 28 trials (1,358 people), GFR after the diet was slightly higher (SMD 0.19, 95% CI 0.07 to 0.31), and the change in GFR did not differ (SMD 0.11, 95% CI -0.05 to 0.27) [9].
- Population
- Adults without chronic kidney disease in randomized trials [5][9][11].
- Sources
- [5], [9], [11]
- Caveats
- Most trials were short and used creatinine-based estimates, so long-term effects are uncertain [5]. Cohorts disagree: in 9,226 Korean adults, the highest protein quarter was linked to 1.32 times the risk of rapid eGFR decline (95% CI 1.02 to 1.73) [12], while a meta-analysis of 6 cohorts (148,051 people) linked higher protein to lower chronic kidney disease incidence (RR 0.82, 95% CI 0.71 to 0.94) [13].
Kidney effects
One trial found no change in kidney markers after 12 weeks of L-carnitine in overweight and obese adults.
The numbers and sources
- How common
- How often is not known: the sources give no rate.
- Effect
- In 68 overweight and obese adults randomized to control, 1,000 mg of L-carnitine a day, exercise, or both for 12 weeks, creatinine and urea did not change significantly in any group [13]. A review of 8 carnitine studies in athletes and bodybuilders found that kidney risks and benefits have not been evaluated in that group [9].
- Population
- 68 overweight and obese adults, mean age 29, for 12 weeks [13]. Athletes and bodybuilders [9].
- Sources
- [13], [9]
- Caveats
- One small trial with blood markers only, at one dose, with no placebo capsule. The review is narrative, and no study in athletes was located [9].
How it compares with the reference method
Mixed results2
Variation from one draw to the next in one person
Shown to vary about 4.4% from one draw to the next within the same person, in a 10-week European study and a pooled estimate.
The numbers and sources
- Compared with
- The same person's results on repeated draws
- Effect
- In 91 healthy Europeans sampled weekly for 10 weeks, within-person variation of serum creatinine was 4.4% (95% CI 4.2 to 4.7) with an enzymatic assay and 4.7% (4.4 to 4.9) with an alkaline picrate assay, with no difference between men and women [16]. The European Federation of Clinical Chemistry and Laboratory Medicine database gives a pooled within-person variation of 4.4%, with lower and upper limits of 2.3% and 4.7%, from 15 included estimates, and variation between people of 16.1% [17]. At a creatinine of 1.00 mg/dL, 4.4% is about 0.04 mg/dL.
- Population
- 91 healthy adults aged 21 to 69 at 6 European laboratories [16]. Healthy adults in the studies the database pools [17].
- Sources
- [16], [17]
- Caveats
- Variation within one person is about a quarter of the variation between people. The database states no threshold for agreement, so the result is given as numbers only [17].
Assay method
Limited evidence: alkaline picrate assays measured creatinine about 4 times less repeatably than enzymatic assays in one study, and a US working group reported bias at lower levels.
The numbers and sources
- Compared with
- Isotope dilution mass spectrometry, the reference method
- Effect
- In samples from 91 adults run in duplicate, analytical variation was 1.1% for an enzymatic method and 4.4% for an alkaline picrate method, which did not meet the imprecision specification the authors derived [16]. A US kidney education program working group reported in 2006 that variability between creatinine measurements made filtration estimates less accurate below 1.5 mg/dL, that many routine methods met the required precision while bias remained, and that standardizing calibration does not correct interference from other substances [18]. The two survey manuals on this page describe one method of each kind. Both are traceable to the reference method, and they print different reference ranges [2][3].
- Population
- 91 healthy adults at 6 European laboratories [16]. A review of routine methods by an expert working group [18].
- Sources
- [16], [18], [2], [3]
- Caveats
- The working group's report dates from 2006 and sets out a plan for standardizing calibration, so it describes assays as they then were. A laboratory report does not always say which method was used [18].
Did not match the reference method3
Muscle mass
One study of 170 healthy adults found serum creatinine rose with lean mass while cystatin C, another filtration marker, did not.
The numbers and sources
- Compared with
- Serum cystatin C measured in the same people
- Effect
- Serum creatinine correlated with body weight and more strongly with lean mass, and cystatin C correlated with neither. People with moderate or intense physical activity had more lean mass (55.3% against 48.5%) and higher serum creatinine (1.04 against 0.95 mg/dL) than sedentary people, with no difference in cystatin C. Lean mass stayed related to creatinine after adjustment for protein and meat intake and physical activity [10]. A kidney guideline lists body builders, extreme sport, eating disorders, above-knee amputation and spinal cord injury as settings where muscle mass alters creatinine apart from kidney function. It also lists anabolic steroids, medications that decrease secretion of creatinine by the kidney tubules, and low-protein, vegetarian, ketogenic and high-protein diets [11].
- Population
- 92 women and 78 men, healthy, grouped as sedentary, mildly active or moderately to intensely active [10].
- Sources
- [10], [11]
- Caveats
- The study did not measure kidney filtering directly, so it shows that creatinine tracks muscle, not by how much any one result is shifted [10]. The reference ranges on this page are printed by sex and not by muscle mass [2][3].
Creatine supplements
Shown to raise serum creatinine about 0.13 mg/dL in pooled trials, with no significant change in kidney filtering measured by a tracer.
The numbers and sources
- Compared with
- Kidney filtering measured with Cr-EDTA, a tracer method that does not rely on creatinine
- Effect
- In 26 randomized trials, creatine supplementation raised serum creatinine by 0.14 mg/dL (95% CI 0.05 to 0.22). Filtering measured by Cr-EDTA did not differ significantly (5.89 mL/min, 95% CI -0.30 to 12.08), nor did serum urea, albuminuria or proteinuria [12]. A second meta-analysis of 20 randomized studies found serum creatinine 0.13 mg/dL higher (95% CI 0.07 to 0.18), with no difference in urea [13].
- Population
- 1,036 participants in 26 trials, healthy people and people with chronic kidney disease [12]. 19 randomized trials and one randomized crossover study [13].
- Sources
- [12], [13]
- Caveats
- The authors of the first analysis attribute the rise to altered creatinine metabolism, not kidney injury, because the tracer measurement did not change. Results across its trials varied widely. The authors of the second call for trials longer than 1 year [12][13].
A cooked meat meal before the blood draw
Shown to raise serum creatinine for hours after a cooked meat meal, from a median of 0.91 to 1.14 mg/dL in one study.
The numbers and sources
- Compared with
- The same people's results before the meal and after a meat-free meal
- Effect
- In 32 people, median serum creatinine rose from 80.5 µmol/L (0.91 mg/dL) before a cooked meat meal to 101.0 µmol/L (1.14 mg/dL) 1 to 2 hours after and 99.0 µmol/L (1.12 mg/dL) at 3 to 4 hours. Meat-free meals had little effect, and the changes were similar by three assay methods [14]. In 80 people, a standardized cooked meat meal with about 54 g of protein raised serum creatinine at every stage of diabetes-related kidney disease studied, and the effect was gone after a 12-hour fast [15]. A kidney guideline describes a rise of about 0.23 mg/dL in one study, reached by 2 hours in some people and 4 hours in others, and states that waiting at least 12 hours after eating meat or fish avoids the effect [11].
- Population
- 17 healthy volunteers and 15 outpatients [14]. 80 people: healthy volunteers and people with diabetes at 4 stages of chronic kidney disease, 16 per group [15].
- Sources
- [14], [15], [11]
- Caveats
- Both studies are small. The second gives no size for the rise in its abstract. Its authors attribute the rise to creatine in meat that turns to creatinine on cooking and is absorbed [15].
What studies tie it to
Linked in research4
Stroke and death at higher levels
Limited evidence: one British cohort of 7,690 middle-aged men linked creatinine above 1.31 mg/dL to 60% more strokes over about 15 years.
The numbers and sources
- Effect
- Median creatinine was 98 µmol/L (1.11 mg/dL). Above 116 µmol/L (1.31 mg/dL), the top tenth, the relative risk of stroke was 1.6 (95% CI 1.1 to 2.1) against all other men after adjustment for cardiovascular risk factors. For major ischemic heart disease, the relative risk at 130 µmol/L (1.47 mg/dL) or above was 1.2 (0.8 to 1.7) after adjustment. Death from any cause and from cardiovascular disease was significantly raised only above the 97.5th percentile, and there was no association with death from cancer [6].
- Population
- 7,690 men aged 40 to 59 from 24 British towns, followed for an average of 14.75 years, with 287 strokes, 967 major ischemic heart disease events and 1,259 deaths [6].
- Sources
- [6]
- Caveats
- One observational cohort of middle-aged men in one country [6]. Studies that convert creatinine to an estimated filtration rate are covered on the eGFR page.
Death in hospital after a rise during the stay
Limited evidence: in one hospital cohort a rise in creatinine of 0.5 mg/dL or more during the stay went with 6.5 times the odds of death.
The numbers and sources
- Effect
- Among adults with two or more creatinine results during a hospital stay, a rise of 0.5 mg/dL or more occurred in 1,237 (13%) and a rise of 2.0 mg/dL or more in 105 (1%). A rise of 0.5 mg/dL or more was associated with 6.5 times the odds of death (95% CI 5.0 to 8.5), 3.5 more days in hospital and nearly 7,500 dollars in added cost, after adjustment for age, sex, diagnosis, severity of illness and chronic kidney disease [7].
- Population
- 9,210 adults with two or more creatinine measurements, among 19,982 admitted to one urban academic medical center [7].
- Sources
- [7]
- Caveats
- Observational, at one center, in people ill enough to be admitted. It concerns a change during a hospital stay, not a single outpatient result [7].
Type 2 diabetes at low levels
Limited evidence: one Japanese cohort of 8,570 men linked creatinine of 0.40 to 0.60 mg/dL to about twice the odds of type 2 diabetes over 4 years.
The numbers and sources
- Effect
- During 4 years, 877 men developed type 2 diabetes. Men with a creatinine of 0.40 to 0.60 mg/dL had an adjusted odds ratio of 1.91 (95% CI 1.44 to 2.54) against men at 0.71 to 0.80 mg/dL. The authors treat low creatinine as a possible stand-in for low skeletal muscle mass [8].
- Population
- 8,570 Japanese men aged 40 to 55 without diabetes at entry [8].
- Sources
- [8]
- Caveats
- One observational cohort of men in one country. Muscle mass was not measured, so the link to muscle is the authors' interpretation [8].
Death in intensive care at low levels
Limited evidence: one cohort of 11,291 intensive care patients linked a baseline creatinine of 0.6 mg/dL or below to about 2.6 times the odds of death.
The numbers and sources
- Effect
- After adjustment for predicted mortality, age, sex, surgery and body mass index, the odds ratio for death in hospital was 2.59 (95% CI 1.82 to 3.61) for a baseline creatinine of 0.6 mg/dL or below and 1.28 (1.03 to 1.60) for 0.6 to 0.8 mg/dL. Median baseline creatinine was 1.1 mg/dL. The authors treat low creatinine as a marker of low muscle mass [9].
- Population
- 11,291 adults admitted to three intensive care units at two hospitals from 2003 to 2006, 1,185 deaths in hospital [9].
- Sources
- [9]
- Caveats
- Retrospective, in critically ill patients, so it does not describe a low result in a person who is well. Muscle mass was not measured [9].
Related
Sources
- US Food and Drug Administration. 21 CFR 862.1225, Creatinine test system. Electronic Code of Federal Regulations. https://www.ecfr.gov/current/title-21/section-862.1225
- Centers for Disease Control and Prevention, National Center for Health Statistics. National Health and Nutrition Examination Survey 2017-2018 Laboratory Procedure Manual: Creatinine, serum, Roche Cobas 6000. Performed by the University of Minnesota Advanced Research and Diagnostic Laboratory. https://wwwn.cdc.gov/nchs/data/nhanes/public/2017/labmethods/BIOPRO-J-MET-Creatinine-508.pdf
- Centers for Disease Control and Prevention, National Center for Health Statistics. National Health and Nutrition Examination Survey 2015-2016 Laboratory Procedure Manual: Creatinine, refrigerated serum, Beckman UniCel DxC 800 Synchron. Performed by Collaborative Laboratory Services. https://wwwn.cdc.gov/nchs/data/nhanes/public/2015/labmethods/BIOPRO_I_MET_CREATININE_DXC800.pdf
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- Baxmann AC, Ahmed MS, Marques NC, et al. Influence of Muscle Mass and Physical Activity on Serum and Urinary Creatinine and Serum Cystatin C. Clinical Journal of the American Society of Nephrology. 2008. https://doi.org/10.2215/CJN.02870707
- Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney International. 2024. https://doi.org/10.1016/j.kint.2023.10.018
- de Souza Almeida A, da Silva LOD, Takahasi BNA, et al. Impact of creatine supplementation on kidney health: a systematic review and meta-analysis. International Urology and Nephrology. 2026. https://doi.org/10.1007/s11255-026-05287-x
- Tsiaras A, Loufopoulos G, Theodoridis X, et al. The Effect of Creatine Supplementation on Kidney Function: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Journal of Renal Nutrition. 2026. https://doi.org/10.1053/j.jrn.2026.04.010
- Preiss DJ, Godber IM, Lamb EJ, et al. The influence of a cooked-meat meal on estimated glomerular filtration rate. Annals of Clinical Biochemistry. 2007. https://doi.org/10.1258/000456307779595995
- Nair S, O'Brien SV, Hayden K, et al. Effect of a Cooked Meat Meal on Serum Creatinine and Estimated Glomerular Filtration Rate in Diabetes-Related Kidney Disease. Diabetes Care. 2014. https://doi.org/10.2337/dc13-1770
- Carobene A, Marino I, Coşkun A, et al. The EuBIVAS Project: Within- and Between-Subject Biological Variation Data for Serum Creatinine Using Enzymatic and Alkaline Picrate Methods and Implications for Monitoring. Clinical Chemistry. 2017. https://doi.org/10.1373/clinchem.2017.275115
- European Federation of Clinical Chemistry and Laboratory Medicine. EFLM Biological Variation Database, meta-analysis estimates, read 2026-11-13. https://biologicalvariation.eu/
- Myers GL, Miller WG, Coresh J, et al. Recommendations for Improving Serum Creatinine Measurement: A Report from the Laboratory Working Group of the National Kidney Disease Education Program. Clinical Chemistry. 2006. https://doi.org/10.1373/clinchem.2005.0525144