It's been discovered that your creatinine levels are fairly reliable indicators of your kidney function. High creatinine level in your system means you have damaged kidneys.

Now, what are the normal levels of creatinine?

Creatinine Levels Chart 

There are 2 possible tests you can take to figure out how creatinine is in your body: serum creatinine test, and creatinine clearance test.

Serum creatinine is measured from your blood (hence the "serum") and is a part of your routine lab report. Creatinine clearance, on the other hand, is taken from your urine sample, requires a bit of preparation before being taken, and is not part of your lab report.

Here's the creatinine levels chart, for easier reference:

Males
Females
Normal Levels

Serum Creatinine (SC)

Clearance Rates (CR)

SC: 0.6-1.2 mg/dl

CR: 97-137 ml/min

SC: 0.5​​​​​-1.1 mg/dl

CR: 88-128 ml/min

Mild Renal Failure

Serum Creatinine (SC)

Clearance Rates (CR)

SC: 1.3-1.9 mg/dl

CR: 56-97 ml/min

SC: 1.2-1.9 mg/dl

CR: 56-88 ml/min

Moderate Renal Failure

Serum Creatinine (SC)

Clearance Rates (CR)

SC: 2.0-4.0 mg/dl

CR: 35-55 ml/min

SC: 2.0-4.0 mg/dl

CR: 35-55 ml/min

Severe Renal Failure

Serum Creatinine (SC)

Clearance Rates (CR)

SC: > 4.0 mg/dl

CR: < 35 ml/min

SC: > 4.0 mg/dl

CR: < 35 ml/min

What is considered as the normal level of creatinine in the blood (a.k.a. serum creatinine) are as follows:

  • approximately 0.6-1.2 milligrams (mg) per deciliter (dL) for adult males
  • approximately 0.5-1.1 mg/dL for adult females.

For creatinine clearance, it is often measured in milliliters per minute (ml/min). What's considered as normal values from this test are as follows: 

  • 97-137 ml/min for males 
  • 88-128 ml/min for females

However, these numbers can vary from lab to lab, or with age. Also, creatinine levels for men are higher because the chemical increases relative to muscle mass. 

Some laboratories might also use different measurements, or test different samples, hence the slightly varying results. It is best to contact your nephrologist to understand your results better.

Types of Creatinine Level Tests

While serum creatinine test and creatinine clearance test both tell you how much of the chemical is in your body, these are both different lab tests.

Creatinine testing

Image_source:_https://cdn1.medicalnewstoday.com/content/images/articles/322/322380/creatinine-blood-test.jpg

Let's learn more about these tests...

Serum Creatinine Test

As mentioned, a serum creatinine test measures your creatinine level in your blood. This test can be scheduled by your doctor based on a few health risks/factors you may have, like: 

  • Type 1 or 2 diabetes, which may cause you doctor to recommend an annual creatinine test;
  • Kidney disease (creatinine tests should be taken at regular intervals, at your doctor's discretion), and;
  • Other illnesses, like high blood pressure (you may be taking medication that affect your kidney functions). 

This is considered a common blood test, and there is usually no prior preparation needed for it. However, your doctor might instruct you about certain things for the test, depending on the conditions above.

Like common blood sample tests, one of your health care team members will extract blood from a vein in your arm with a needle. He/she will then send this sample to a laboratory for analysis.

Creatinine Clearance Test

The creatinine clearance test is a bit different from the serum creatinine test. What this test does is compare the creatinine levels between your urine and your blood.

You will be tasked to collect your urine within a 24-hour time period, then get some blood taken. Your doctor might also give you a few specific instructions, so make sure you follow them to the letter.

Urine Test

Image_source:_https://www.fastmed.com/wp-content/uploads/urine-1200x800.jpg

The urine collection part of the test involves only normal urination. Just don't forget to collect every time you urinate during the 24-hour duration. The blood extraction part will be the same as instructed above.

--oOo--

When you have kidney disease, your creatinine levels will often be above normal. As you may well know, kidney disease is irreversible, but you may be able to prevent further damage with the appropriate treatment and proper management.

To know more about creatinine tests and other key indicators of kidney damage, download your own copy of the Renal Progress eBook below.

Now, you might ask: what causes a rise in one's creatinine?

Reasons for High Creatinine Levels

Your creatinine levels may temporarily increase due to certain conditions. 

Some of these can be more severe than others, but that just means that you can take steps to get your creatinine levels to normal range.

  • Dehydration
    Not drinking enough water doesn't help your kidneys filter out creatinine from your system effectively.
  • Renal Failure / Impairment
    With your kidneys damaged, creatinine is not successfully filtered out from your body through glomerular filtration, which is the outflow of filtered fluid passing through your kidney.
Hands holding a kidney frame
  • Muscle Destruction
    If you have a condition which causes the breakdown of your muscle tissues, those can get into your bloodstream and cause further impairment of your kidneys.
  • Increased Meat Intake
    A high intake of meat products can increase the amount of protein in your body. Protein, when broken down, is used up by your muscles, which in turn results to an increase in creatinine production.
  • Hypothyroidism
    A dysfunction in your thyroid gland can influence your kidney function by decreasing your kidneys' ability to filter waste out of your body.
  • Certain Medications
    Some prescribed medications to cure other ailments like certain antibiotics and acid blockers can raise your creatinine in your blood and cause a false alarm regarding your kidney's condition.
Hands holding Medications
  • Supplements with 'Creatine' Component
    Creatine, an amino acid that the body produces, can also be produced synthetically and added as part of body supplements, especially for muscle building. Unfortunately, high doses of this chemical can aggravate the damage on your kidneys.

So, how do you bring down your creatinine levels?

A more in-depth guide to improving your kidney numbers, like GFR and BUN, is available inside our Renal Progress printable eBook. Click the banner below if you want to get a free copy.

How to Lower Creatinine Levels

1. Hydrate yourself properly. 

Women Holding Glasses of Water

A normal person is advised to drink about 6-8 glasses (8-oz / 250-ml) of water each day. As mentioned above, dehydration is one of the causes of elevated creatinine levels.

However, this basic rule might not apply to you, especially when you're at Stage 3 and above of CKD. Too much liquid in the body can increase blood pressure which, in turn, puts more stress to your body filters.

Best advice: consult your nephrologist / dietitian about setting a proper limit to your fluid intake.  

2. Drink green tea. 

CKD patients need to be careful about using herbal medicines. Although they do help on curing certain illnesses, some herbal products and remedies can actually worsen your condition due to their potassium and phosphorus content.

Herbal Tea

That being said, green tea can urge your kidneys to produce more urine, which will help you pass more creatinine out of your body.

Advice #1: drink about 8 oz (250 ml) or herbal / green tea a day to stimulate your kidneys.

Advice #2: talk to your doctor about salvia.

Salvia is an herb that's been used to treat chronic renal insufficiency in China. Japanese researchers have also reported that a component of said herb, lithospermate B, enhances plasma blood flow and helps increase creatinine clearance rate.

Meet with your doctor to discuss if and how you could use salvia to your benefit. Do not start using salvia without consulting with your doctor.

3. Exercise within your body's limits; do not strain yourself.

Don't get this wrong: exercise is important for your body, of course. Just because you have CKD doesn't mean you should slack off and let your muscles atrophy.

women exercising

However, doing vigorous exercises makes your body expend energy faster and induce a buildup of creatinine in your system.

Best advice: try your hand at walking and yoga.

4. Get enough sleep.

When you're asleep, most (if not all) of your body functions slow down. This means that the rate of creatinine production in your body also slows. This allows your kidneys to steadily filter out creatinine from your system before it can build up even more.

Alarm clock with a man in the background

Also, the slowing down of your entire body's systems allows your kidneys a little rest and lets them recover and heal from the day's work. So getting enough hours of sleep is tantamount to giving your kidneys enough hours of rest, too.

5. Consult your doctor about certain medications and creatine-containing supplements.

Some medications that cause a rise in your creatinine levels are the following:

  • Acid blockers (used for acid reflux and heartburn) 
  • Certain antibiotics (used to treat infections)
  • High cholesterol medications (for heart disease patients)

If you have been taking medicines like these, there is a chance you may been misdiagnosed for having kidney disease.

But, if it's been confirmed that you have kidney disease, these medications still might pose danger on your kidneys due to their side-effect of raising your creatinine level.

Advice #1: consult your doctor about alternatives to these medications. DO NOT change your medications without consulting with your doctor, and DO NOT start self-medicating.

Advice #2: lay off the creatine supplements. You can still get enough creatine for your body from protein foods.

These 5 steps is a good start to lower your creatinine levels. If you want to learn more about tracking and improving your progress,  click the banner below to download the printable Renal Progress eBook.

Creatinine Levels and Renal Diet

Your diet also plays an important role in controlling your creatinine levels. 

A study published in the National Center for Biotechnology Information (NCBI) website has discovered that patients undergoing a vegetarian diet did not experience any unusual increase in creatinine levels, and that "the values measured were within normal range."

Figure 1: Serum creatinine in volunteers who ate cooked meat during duration of the study

Figure 2: Serum creatinine in volunteers who ate vegetarian meals during duration of the study

Images'_source:_https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5047024/

Apparently, cooking meat converts creatine stored in the skeletal muscles into creatinine. This is why the patients consuming meat during the study experienced a rise in their serum creatinine levels. To read more about this, see link on the sources below.

The rise in creatinine may be temporary, but for someone with kidney disease, this could make all the difference.

This also supports the advice we have for CKD patients to avoid excessive meat intake, which could cause protein buildup and harm the kidneys. 

If you're thinking of considering a vegetarian diet because of this, but you're not sure which foods are good for your kidneys, check out this list of vegetables and fruits (serving size is 1/2 cup unless otherwise stated):

FRUITS
VEGGIES
  • apples (1 medium fruit)
  • applesauce or juice
  • apricots, canned in juice
  • blackberries
  • blueberries
  • cherries
  • cranberries
  • fruit cocktails
  • grape, including juice
  • grapefruit (1/2 of fruit)
  • peaches (1 small fruit)
  • pineapple, including juice
  • plum/s (1 whole fruit)
  • raspberries
  • strawberries
  • tangerine (1 whole fruit)
  • watermelon (1 cup)
  • alfalfa sprouts
  • asparagus, raw (6 spears)
  • beans, green or waxed
  • broccoli, raw or cooked
  • cabbage, green and/or red
  • carrots, cooked
  • cauliflower
  • celery (1 stalk)
  • corn, fresh (1/2 ear)
  • cucumber
  • eggplant
  • kale
  • lettuce
  • onions
  • parsley
  • peas, green
  • peppers
  • radish
  • rhubarb
  • watercress
  • yellow squash
  • water chestnuts, canned
  • white mushrooms, raw

For a printable version of this list, download our free Vegetarian Food List eBook below.

However, we still need the amino acids that we get from meat. They still serve an important purpose in strengthening our bodies. But, because of the condition you have, you will need to find the right balance on your diet and set limits on your nutrient intake.


Conclusion

To summarize...

Creatinine is a great indicator of kidney disease and damage. An elevated creatinine level in the blood or in the kidney can mean you have CKD.

There are different possible reasons your creatinine can increase, like dehydration, an increase in your meat intake, or creatine supplements, among others. 

You can determine your creatinine levels by undergoing a serum creatinine blood test or creatinine clearance test. Results can vary depending on your age, gender, or the lab that processed the sample. Your doctor can help you understand these results.

There are a few ways to help you control your creatinine levels. Changing to a low-protein diet or a vegetarian diet is one of them. You can consult your doctor on how you can implement these.

In conclusion, your creatinine is a very important part of your tracking and monitoring. Keeping control of your creatinine levels will help you manage your kidney condition better and help you eventually delay dialysis.

P.S. Our RenalTracker Support Group in Facebook is always available to anyone who needs help and/or wants to help. Click here check out our RenalTracker Support Group.

Sources:

Creatinine test - Mayo Clinic;

https://www.mayoclinic.org/tests-procedures/creatinine-test/about/pac-20384646


What is the normal range for a creatinine blood test? - Medical News Today;

https://www.medicalnewstoday.com/articles/322380.php


The Use of Salvia for Patients with Renal Failure; Subhuti Dharmananda, Ph.D. - Institute of Traditional Medicine;

http://www.itmonline.org/arts/salviarenal.html


High Creatinine Levels on Your Blood Test? — Taking These 4 Drugs Can Cause a False Alarm; Dr. Sharon Orrange - GoodRx;

https://www.goodrx.com/blog/drugs-cause-false-high-creatinine-levels-blood-test/


Effect of Diet on Serum Creatinine in Healthy Subjects During a Phase I Study; Pimenta, Jensen, Jung, Schaumann, Boxnick, and Truebela - National Center for Biotechnology Information;

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5047024/