Kidney Diet Tips

Kidney Health 101: What is Creatinine?

Learning that you have kidney disease can come with a lot of questions. And it can often feel like you’re learning a whole new vocabulary as you talk with your doctor and manage your health. One term you may have discussed with your doctor is creatinine. It is pronounced kree· a· tuh· neen.

Creatinine Basics

Creatinine is a normal waste product found in your blood that your muscles create. The more muscle you have, the more creatinine you’ll produce. On average, men will have higher creatinine levels in their blood than women because of higher muscle mass.

When kidneys filter the body’s blood, creatinine is one of the waste products that is filtered out into urine. So if you have kidney disease, your body may not be getting rid of creatinine effectively enough. As a result, creatinine starts to build up in your blood.

You might not experience any symptoms as your creatinine levels rise, but symptoms may also develop gradually. If you’ve experienced a loss of appetite, nausea and vomiting, itching, weakness or flu-like symptoms, these symptoms might be due to high levels of creatinine and other waste buildup.

Creatinine and Creatine

Creatinine is different from creatine, which you may have heard of as a popular supplement for people who work out. Creatine is actually a chemical compound found in muscles that works to enhance muscle strength and performance. However, many people will also purchase and use creatine as a supplement to improve their strength. As creatine is broken down in your body, the waste product it creates is creatinine. Creatine supplements are not recommended for people with kidney disease.

Serum Creatinine vs. Creatinine Clearance

Two other terms that may come up as you talk with your doctor about your kidney health are “serum creatinine” and “creatinine clearance.” These terms refer to two different ways to measure your kidney health.

Serum creatinine is a blood test that determines how much creatinine is in the bloodstream. Your serum creatinine is used to determine your glomerular filtration rate (GFR), a measurement of kidney function. Your doctor will interpret your serum creatinine results and explain what this means for your kidney health.

If you know your serum creatinine level, DaVita’s GFR Calculator can also help you figure out your GFR. Keep in mind, though, that talking with your doctor can help you better understand the other factors that help determine if you have kidney disease as well as what stage you may be in.

Creatinine clearance (Ccr or CrCl) measures how much creatinine your body is able to pass through urine, indicating how well your kidneys are filtering waste. This requires both a urine test and a blood test. This test happens over the course of 24 hours. During that time, all urine is collected so that your doctor can compare how much creatinine leaves your body with how much you have in your bloodstream.

Creatinine by the Numbers

As you may already know, kidney disease can progress over time through five stages. Each stage refers to how effectively your kidneys are filtering your blood. Your doctor can talk with you about what your creatinine level is. Generally, most men with normal kidney function have approximately 0.6–1.2 milligrams/deciliters (mg/dL) of creatinine while most women will have .5–.11 mg/dL of creatinine.

Remember that other factors—such as body size, activity level and medications—can all affect your creatinine levels. So it’s best to talk with your doctor about what a healthy creatinine level is for you and what you can do to help keep your levels in check and manage your kidney health.

Additional Kidney Diet Resources

Visit and explore these diet and nutrition resources:

DaVita Food Analyzer

DaVita Dining Out Guides

Today’s Kidney Diet Cookbooks

DaVita Kidney-Friendly Recipes

Diet and Nutrition Articles                                                      

Diet and Nutrition Videos

Kidney Smart® Virtual Classes

This article is for informational purposes only and is not a substitute for medical advice or treatment. Consult your physician and dietitian regarding your specific diagnosis, treatment, diet and health questions.

Kidney Diet & Health Tips Team

Kidney Diet & Health Tips Team

The Kidney Diet & Health Tips Team offers insights and tips on kidney health.