A Guide to Understanding Your Comprehensive Metabolic Panel (CMP)

A metabolic workup, which is also referred to as a comprehensive metabolic panel, is a set of blood tests that can provide your doctor with important information about the health of your blood sugars, liver, electrolytes, kidneys, and blood proteins. 

The results of this blood test can provide your doctor with unique insight into your health and can help them to pin down a diagnosis disease or an illness. In addition, a comprehensive metabolic panel allows your doctor to monitor chronic diseases such as kidney disease or high blood pressure. 

If you’re interested in learning more about a comprehensive metabolic panel and what exactly is tested when you get a CMP, keep reading!

What Is a Comprehensive Metabolic Panel? 

There are two different types of panel tests that your doctor can request when looking to learn more about your health: a basic metabolic panel (BMP) and a comprehensive metabolic panel (CMP). 

Typically, a Comprehensive Metabolic Panel (CMP) test will require that you fast for ten to twelve hours before your blood is drawn. This blood test not only looks to see if there’s any sort of electrolyte imbalance in your blood, but it’ll also test to see if your blood sugar levels are at an abnormal range, as well as how efficiently your blood is being filtered. 

A CMP test will also take a look to see how well your liver is working by measuring the levels of substances that your liver is producing. 

What Is a Lab Reference Range? 

Before we dive into talking about the key biomarkers in a CMP test, we’re going to discuss the importance of a lab reference range. 

If upon receiving your lab results you notice a mark that says that your test results are outside of the lab’s reference range, don’t panic.

A reference range is a set of numerical values (including both the lower limits and the upper limits) of a lab test that have been based upon a group of healthy people. The range of the limits can vary based upon specimen type (such as spinal fluid, urine, blood), age, and sex. 

A reference value is a value that’s expected to be found in a healthy person’s numbers. Sometimes, these values are called ‘normal’ values. By comparing your test results with a reference value, your personal value may be outside of a reference range.

Abnormal Findings

When you go back to your doctor, you and the medical professional you’re seeing will look over the test results that you received to see if your personal numbers fall outside of an expected value of a healthy person. If a medical professional decides that the value is outside of the expected range, it could be a key to diagnosing a disease or illness.

However, you need to keep in mind that a normal result in one lab may be an abnormal result in another lab. Reference ranges sometimes vary from lab-to-lab, due to the different testing equipment, analysis techniques, and chemical reagents that are used when doing testing. 

In addition, an abnormal result doesn’t mean that you’re unhealthy or sick. Reference values are a statistic that are based upon the average healthy person. Your abnormal result may not be abnormal for your body, which is why it’s so important to discuss the results of your blood work with your healthcare provider.

What Are the 19 Key Biomarkers in a Comprehensive Metabolic Panel Test?

There are nineteen key biomarkers that the CMP test measures. Here’s a list of what those biomarkers are and what the clinical reference range for each biomarker through Quest Diagnostics, the laboratory that processes tests ordered through Ulta Lab Tests.

Note that the test results for the exact clinical reference ranges for tests ordered through Ulta Lab Tests are reported back specifically for your age and gender.

1. Glucose


Glucose is a type of sugar that your body uses for getting its energy. If your glucose levels are too high, it may be a sign that you’re pre-diabetic or diabetic.

In order for your body to be able to function at a healthy level, it must have a steady, constant amount of glucose to use.

The clinical reference range for glucose is:

Fasting Reference Interval 65-99 mg/dL
Non-fasting Reference Interval 65-139 mg/dL

2. Blood Urea Nitrogen 

Also referred to as BUN, blood urea nitrogen is one of the compounds that’s filtered out of your blood by your kidneys. Having a Comprehensive Metabolic Panel test completed will verify the levels of BUN found in your blood, which will let your healthcare provider know if your kidneys are properly functioning.

The clinical reference range for BUN in females by age measured in mg/dL is:

  • <1 Month 3-17 mg/dL
  • 1-11 Months 4-14 mg/dL
  • 1-3 Years 3-14 mg/dL
  • 4-19 Years 7-20 mg/dL
  • ≥20 Years 7-25 mg/dL

The clinical reference range for BUN in males by age measured in mg/dL is:

  • <1 Month 4-12 mg/dL
  • 1-11 Months 2-13 mg/dL
  • 1-3 Years 3-12 mg/dL
  • 4-19 Years 7-20 mg/dL
  • 20 Years 7-25 mg/dL

3. Creatinine

Creatinine is another compound that’s filtered out of your blood by your kidneys. A CMP test will make sure that there’s a low level of creatinine in your body, which will confirm that your kidneys are working effectively.

The clinical reference range for creatinine in females by age measured in mg/dL is:

  • ≤2 days 0.79-1.58
  • 3-27 days 0.35-1.23
  • 1 month-9 years 0.20-0.73
  • 10-12 years 0.30-0.78
  • 13-15 years 0.40-1.00
  • 16-17 years 0.50-1.00
  • 18-19 years 0.50-1.00
  • 20-49 years 0.50-1.10
  • 50-59 years 0.50-1.05
  • 60-69 years 0.50-0.99
  • 70-79 years 0.60-0.93
  • ≥80 years 0.60-0.88


The clinical reference range for creatinine in males by age measured in mg/dL is:

  •  ≤2 days 0.79-1.58
  • 3-27 days 0.35-1.23
  • 1 month-9 years 0.20-0.73
  • 10-12 years 0.30-0.78
  • 13-15 years 0.40-1.05
  • 16-17 years 0.60-1.20
  • 18-19 years 0.60-1.26
  • 20-49 years 0.60-1.35
  • 50-59 years 0.70-1.33
  • 60-69 years 0.70-1.25
  • 70-79 years 0.70-1.18
  • ≥80 years 0.70-1.11

4. Bun/Creatinine Ratio

By looking at the BUN to creatinine ratio, a healthcare provider will be able to understand an underlying cause of what’s causing the concentration levels to be elevated. The clinical reference range for the ratio of BUN/creatinine is between  6-22 (calc).

5. eGFR African American

eGFR stands for estimated glomerular filtration rate. This rate is based upon the amount of creatinine found in your blood. This biomarker tells healthcare professionals how efficiently your kidneys are functioning.

The eGFR is calculated by looking at a person’s sex, race, age, and creatinine level. The reason why there are two panels for eGFR is that studies have shown that African Americans have a higher GFR than Caucasians. This is because African Americans have a large amount of muscle mass and have a higher creatinine generation rate.

In order to discover a healthy level of eGFR for you, use the Bedside Schwartz equation.

As mentioned above, the eGFR biomarker shows the level of creatinine found in your bloodstream. The level will vary based on age, sex, and ethnicity.

A healthy rate of GFR for non-African American patients is usually **≥60 mL/min/1.73m2** (which is the surface area of your body). You can use the Bedside Schwartz calculator to help you discover this number.

6. eGFR Non-AFR American 

As mentioned above, the eGFR biomarker shows the level of creatinine found in your bloodstream. The level will vary based on age, sex, and ethnicity. 

A healthy rate of GFR for non-African American patients is usually >90 mil for 1.73m2 (which is the surface area of your body). You can use the Bedside Schwartz calculator to help you discover this number. 

7. Sodium

Sodium is one of the biomarkers that’s measured to make sure that your body has a healthy level of electrolytes. This biomarker is one of four compounds that’s responsible for making sure that your body has a balance in it’s acid-base and that your fluid levels are controlled.

The clinical reference range for sodium is 135-146 mmol/L

8. Potassium

Potassium is another one of the biomarkers that’s measured to make sure your body has an adequate amount of electrolytes. Potassium is another one of the compounds that makes sure your body has it’s acid-base balanced and that the levels of fluid are controlled in your body.

The clinical reference range for potassium in your blood, based on age is:

  • ≤1 Week 3.2-5.5 mmol/L
  • 8-27 Days 3.4-6.0 mmol/L
  • 1-5 Months 3.5-5.6 mmol/L
  • 6 Months-1 Year 3.5-6.1 mmol/L
  • 2-19 Years 3.8-5.1 mmol/L
  • ≥20 years 3.5-5.3 mmol/L

9. Chloride

Chloride is another biomarker that’s used for making sure your body has a healthy amount of electrolytes. Chloride is also another contributing compound to your body’s fluid levels and controlled acid-base.

The clinical reference range for chloride is 98-110 mmol/L.

10. Carbon Dioxide

Did you know that carbon dioxide is also measured to make sure your body has a normal level of electrolytes?

Carbon dioxide also plays a role in making sure that the acid-base in your body is properly balanced and that your body is able to keep control of having a healthy level of fluids.

The clinical reference range for CO2in your blood is 20-32 mmol/L.

11. Calcium

Making sure that your body has adequate levels of calcium in your blood is one of the parts of testing your electrolyte levels. Your nerves and muscles depend on calcium to work efficiently.

Being one of the most important minerals in your body, it also plays a huge role in making sure that your blood is clotting properly.

The clinical reference range for calcium in females by age measured in mg/dL is:

  • <1 month: 8.4-10.6
  • 1-11 months: 8.7-10.5
  • 1-3 years: 8.5-10.6
  • 4-19 years: 8.9-10.4
  • 20-49 years: 8.6-10.2
  • \>49 years: 8.6-10.4

The clinical reference range for calcium in males by age measured in mg/dL is:

  • <1 month: 8.4-10.6
  • 1-11 months: 8.7-10.5
  • 1-3 years: 8.5-10.6
  • 4-19 years: 8.9-10.4
  • 20-49 years: 8.6-10.3
  • \>49 years: 8.6-10.3

12. Total Protein

Combined with Albumin, total protein is responsible for making sure that your body is able to build muscles, maintain muscles, as well as organ tissue, bones, and blood.

If there’s a low level of total protein that’s found in your blood, it may be a sign that you’re not eating enough protein in your diet.

It could also be a sign that there’s an acceleration of protein breakdown, which is a symptom of kidney disease.

An expansion of plasma found in the total protein levels can cause your blood to become diluted, which is a symptom of congestive heart failure.

Total protein measures the amount of albumin and other proteins found in the serum. The serum is the liquid part of blood that remains after a blood clot has been formed.

The clinical reference range for total protein in females by age measured in g/dL is:

  • <1 Month 4.2-6.2
  • 1-5 Months 4.4-6.6
  • 6-11 Months 5.6-7.9
  • 1-19 Years 6.3-8.2
  • ≥20 Years 6.1-8.1


The clinical reference range for total protein in males by age measured in g/dL is:

  • <1 Month 4.1-6.3
  • 1-5 Months 4.7-6.7
  • 6-11 Months 5.5-7.0
  • 1-19 Years 6.3-8.2
  • ≥20 Years 6.1-8.1

13. Albumin

Albumin also plays a vital role in making sure your body is able to maintain and build bones, blood, muscles, and organ tissue. If the levels in your body are too low, it could also be a sign that you’re not eating enough protein or that you have poorly functioning liver or kidneys.

This compound is a protein that’s formed in the liver and plays a major role in making sure your blood clots properly, as it’s the largest protein found in serum.

In addition, albumin is responsible for being a carrier protein for ions and small molecules, as well as a source of amino acid for the metabolism of your tissue, and for maintaining a healthy level of osmotic pressure. Osmotic pressure is responsible for preventing any sort of fluid from leaking outside of your blood vessels.

The clinical reference range for albumin in your blood is 3.6-5.1 g/dL for people of all ages.

14. Globulin

Globulin is another class of protein that’s found in your blood. Globulin makes up for about 40% of the proteins found in your bloodstream. There is a variance in the type of group that globulin proteins are, some of which include; hormones, carrier proteins, antibodies, and enzymes.

The clinical reference range for globulin in your blood is 1.9-3.7 g/dL for people of all ages.

15. Albumin/Globulin Ratio

The albumin and globulin ratio is often referred to as the A/G ratio. The A/G ratio measures the total protein, the total albumin, and then calculates the total level of globulin. This is calculated by subtracting total protein from albumin.

In a healthy body, there should be a little more albumin found in your blood than globulin. However, the A/G ratio may chance whenever the levels of albumin and total proteins change their relationship to each other (by decreasing or increasing). Based on the A/G ratio, healthcare providers may be able to pinpoint a disease based on the relative numbers of globulin and albumin found in your blood.

The Albumin/Globin calculation clinical reference range is 1.0-2.5.

16. Total Bilirubin

A CMP test measures the total level of bilirubin found in your blood, as bilirubin is a waste product that’s produced by your liver. This enzyme is responsible for taking old and damaged red blood cells, breaking them down, and recycling them.

The clinical reference range for total bilirubin by age measured in mg/dL is:

  • ≤1 Day ≤5.1
  • 2 Days ≤7.2
  • 3-5 Days ≤10.3
  • 6-7 Days ≤8.4
  • 8-9 Days ≤6.5
  • 10-11 Days ≤4.6
  • 12-13 Days ≤2.7
  • 14 Days-9 Years 0.2-0.8
  • 10-19 Years 0.2-1.1
  • ≥20 Years 0.2-1.2

17. Alkaline Phosphatase

The alkaline phosphate is an enzyme that’s found in the liver, as well as other tissues.

This biomarker measures the functioning of your liver. If levels are too high, it may be a sign that your liver is not working properly, or you have a form of a bone disorder.

The clinical reference range for alkaline phosphate in females by age measured in mg/dL is:

  • <1 Month 48-406
  • 1-11 Months 124-341
  • 1-3 Years 108-317
  • 4-6 Years 96-297
  • 7-9 Years 184-415
  • 10-12 Years 104-471
  • 13-15 Years 41-244
  • 16-19 Years 47-176
  • 20-49 Years 33-115
  • ≥50 Years 33-130

The clinical reference range for alkaline phosphate in males by age measured in mg/dL is:

  • <1 Month 75-316
  • 1-11 Months 82-383
  • 1-3 Years 104-345
  • 4-6 Years 93-309
  • 7-9 Years 47-324
  • 10-12 Years 91-476
  • 13-15 Years 92-468
  • 16-19 Years 48-230
  • ≥20 Years 40-115

18. ALT

ALT stands for alanine aminotransferase and is also commonly referred to as SGPT. This is an enzyme that’s found in the majority of the cells in your kidneys and liver. The CMP test measures the levels of AST found in your blood to see if there are any signs of liver damage.

The clinical reference range for ALT in females by age measured in U/L is:

  • <1 Month 3-25
  • 1-11 Months 3-30
  • 1-3 Years 5-30
  • 4-12 Years 8-24
  • 13-15 Years 6-19
  • 16-19 Years 5-32
  • ≥20 Years 6-29


The clinical reference range for ALT in males by age measured in U/L is:

  • <1 Month 3-25
  • 1-11 Months 4-35
  • 1-3 Years 5-30
  • 4-12 Years 8-30
  • 13-15 Years 7-32
  • 16-19 Years 8-46
  • ≥20 Years 9-46

19. AST

AST is an abbreviation of aspartate aminotransferase, which is also referred to as SGOT. This enzyme makes up the majority of the cells that are found in the liver and heart.

The CMP panel tests the levels of AST found in your blood to see if there are any signs of liver damage in your bloodstream.

The clinical reference range for AST in females by age measured in U/L is:

  • <1 Month 3-49
  • 1-11 Months 3-79
  • 1-3 Years 3-69
  • 4-6 Years 20-39
  • 7-19 Years 12-32
  • 20-44 Years 10-30
  • ≥45 Years 10-35


The clinical reference range for ALT in males by age measured in U/L is:

  • <1 Month 3-51
  • 1-11 Months 3-65
  • 1-3 Years 3-56
  • 4-6 Years 20-39
  • 7-19 Years 12-32
  • 20-49 Years 10-40
  • ≥50 Years 10-35

Take Control of Your Health

comprehensive metabolic panel (CMP) is an incredibly useful tool to use to help get a diagnosis for an illness or disease that you suspect that you may have. It’s also a great way to check up on your health to make sure you’re on the right track for preventing any possible health conditions.

If you need help understanding the health, we’d love to help. We offer the CMP test as part of our selection of 2,000 lab tests, and we provide explanations on each biomarker.

You can select your lab tests, order directly online, choose a convenient patient service center near you, and review your test results typically in 1 to 2 days after your blood is collected.

Are you interested in ordering your own comprehensive metabolic panel test? Feel free to contact us with any questions you may have or click here to order your CMP test directly.