CMP vs BMP Lab Test

If you have ever had your blood tested, you may have heard your doctor discuss a “CMP” or a “BMP” lab test. These two blood tests are similar in that they both test for substances in the blood related to metabolism. This guide examines the CMP and BMP blood tests and the differences between them.

What is a CMP?

CMP stands for Comprehensive Metabolic Panel. A CMP tests for 14 different substances in the blood, including:

• Aspartate aminotransferase (AST or SGOT)
• Alanine aminotransferase (ALT or SGPT)
• Alkaline phosphatase (ALP)
• Blood urea nitrogen (BUN)
• Carbon dioxide
• Creatinine
• Total Protein
• Potassium
• Glucose
• Chloride
• Albumin
• Calcium
• Bilirubin
• Sodium

CMP Blood Test

The first eight substances listed above are also part of the BMP test. The CMP Blood test detects additional substances that help evaluate liver and kidney health.

• Aspartate aminotransferase (AST or SGOT) is a liver enzyme that may indicate liver damage.
• Alanine aminotransferase (ALT or SGPT) is a liver enzyme that can indicate liver damage.
• Alkaline phosphatase (ALP) is a type of liver enzyme that can help evaluate for liver or bone issues.
• Total protein looks at the overall protein levels in the body.
• Albumin helps to evaluate kidney and liver function.
• Bilirubin is created by the liver when red blood cells dissolve, so it can help to indicate if the liver is functioning correctly.

What is BMP?

BMP stands for Basic Metabolic Panel. BMPs test for 8 of the same 14 substances that CMP tests for; including:

• Blood urea nitrogen (BUN)
• Carbon dioxide
• Potassium
• Creatinine
• Chloride
• Glucose
• Calcium
• Sodium

BMP Blood Test

A BMP is typically used to evaluate electrolyte balance, blood sugar, and how the body filters blood. The BMP test gives a general metabolism overview. The components of a BMP assess the body in the following ways:

• Blood urea nitrogen (BUN): This value measures the amount of urea nitrogen in your blood, representing kidney health.
• Carbon dioxide: Carbon dioxide is typically expelled from the body when you breathe. Abnormal carbon dioxide levels may indicate an issue with the lungs or kidneys.
• Potassium:  another vital electrolyte for fluid balance and can also give an idea of cardiac function.
• Creatinine: when kidneys are healthy, they filter creatinine out of the blood. Looking at creatinine levels helps to evaluate kidney function. When creatinine levels are high, the kidneys may not be functioning correctly.
• Chloride: Chloride levels can help your doctor evaluate lung and kidney health and acid-base balance.
• Glucose: Glucose is another name for sugar. By looking at glucose levels, your doctor can know if your blood sugar levels are running higher or lower than they should be.
• Calcium: Calcium helps evaluate kidney, bone, and thyroid health.
• Sodium: This electrolyte helps your doctor understand your body’s fluid balance.

Differences between CMP and BMP

Both the CMP and BMP give a good picture of your metabolic health. However, A CMP looks closer at levels that evaluate liver function. A BMP is a more general test that can help evaluate kidney or heart function issues.

When are CMP and BMP ordered?

Some common reasons for a BMP may include the following:

• Evaluating kidney function
• Evaluating blood sugar balance
• Looking at the electrolyte balance in the body
• Looking at the acid-base balance (pH) in the blood

A CMP may be helpful for many of the same reasons as a BMP. If your doctor has concerns about your liver function or wants to get a closer look at your health by testing for additional substances in the blood, they may order a CMP instead of a BMP.

Preparing for the CMP and BMP

You may be required to fast for eight hours to prepare for a CMP or BMP blood test. Fasting means refraining from eating or drinking anything, or, in some instances, you may be able to drink water. Due to the potential fasting requirement, scheduling this type of test early in the morning is recommended to accommodate an overnight fast and get the test done first thing in the morning.

Your doctor will provide you with specific instructions regarding your preparation for the blood test. When testing is time, you can expect a small needle to stick in one of your veins. Usually, this will be in the crease of your arm, opposite the elbow. A nurse will place a needle into your veins and quickly draw a small vial of blood.

Summary

When it comes to comparing CMP vs BMP blood tests, the two are very similar. The primary difference is that a CMP tests for a few more values than a BMP, which can give your doctor a complete picture of your overall health, including liver health. If you are concerned or have any questions regarding your regular blood work, talk with your doctor about these concerns. Understanding what each test looks at is essential to fully comprehend the methods and reasoning behind your testing.

• In-Home Lab Tests
• Micronutrient Testing
• Heavy Metals Testing