Regular blood testing is one of the most important ways to keep track of your overall physical well-being.
Getting tested at routine intervals can allow you to see the way your body changes over time and empower you to make informed decisions about your health.
Your doctor will typically recommend that you get routine blood work at least once a year, around the same time as your yearly physical.
But this is the bare minimum. There are several major reasons you may want to get blood tests more often than that:
Talk to your doctor first if you want to get certain tests more often than once a year.
Some of the most common routine tests are:
Some other tests that you may want include:
Everything you eat and drink contains vitamins, proteins, and other nutrients that can cause the related levels in your blood to temporarily spike or drop.
Fasting for 8–12 hours helps ensure that blood test results are free from these variables, making your test results as accurate as possible.
Some common tests that may require fasting include:
Results may take anywhere from a few hours to a few days to become available. Here's an overview of how long some common tests may take:
This can depend on the specific lab where you get tested or how many tests you get done at once. If you order multiple tests, you may not get the complete results until all of the tests are completed.
Sometimes a lab will only release results to your doctor, who reviews them and then releases them to you.
Your doctor typically orders blood tests for you during a physical, checkup, or an appointment intended for a specific condition.
Blood testing is usually partially or fully covered by insurance. Ordering tests through your medical provider ensures that you're not paying too much. Your doctor can also advise you on how to choose testing facilities that are reliable, well-managed, or convenient for you.
It's possible to order your own blood tests without a doctor or even health insurance, but it's not recommended. You may end up paying the full cost by not going through an insurance plan, which can be expensive.
And some blood testing facilities may not give you accurate results. One infamous case of this is Theranos, a Palo Alto, California, biotechnology firm shut down in 2018 when an investigation uncovered lies and fraud around the accuracy of its private blood testing technology.
Let's take a closer look at tests for adults to have done regularly.
A routine complete blood count (CBC) test checks for levels of 10 different components of every major cell in your blood: white blood cells, red blood cells, and platelets. Important components measured by this test include red blood cell count, hemoglobin, and hematocrit.
Here's the typical range of results:
Abnormal levels of these components may indicate:
Based on your results, your doctor will order follow-up tests to confirm abnormal levels and a possible diagnosis.
A basic metabolic panel (BMP) checks for levels of certain compounds in the blood, such as:
This test requires you to fast for at least eight hours before your blood is drawn.
See our chart for normal results.
Abnormal results may indicate kidney disease, diabetes, or hormone imbalances. Your doctor will perform follow-up tests to diagnose any of these conditions.
A complete metabolic panel (CMP) includes all the measurements of a BMP as well as additional proteins and substances related to liver function:
The same conclusions can be drawn from a CMP as from a BMP for the same substances that a BMP covers. Other abnormal levels can also indicate underlying conditions, such as:
This test checks levels of two types of cholesterol:
HDL is 'good' because it removes harmful substances from your blood and helps the liver break them down into waste. LDL is 'bad' because it can cause plaque to develop in your arteries, increasing your risk of heart disease.
You need to fast for at least 8 hours before this test.
Here are the ranges for each type:
Normal levels can also vary by age.
A thyroid panel, or thyroid function test, checks how well your thyroid is producing and reacting to certain hormones, such as:
Your thyroid, a tiny gland in your neck, helps regulate bodily functions like your mood, energy level, and overall metabolism.
Here are normal results:
Abnormal levels of these hormones can indicate numerous conditions, such as low protein levels, thyroid growth disorders, and abnormal levels of testosterone or estrogen.
Enzymes are proteins that help your body accomplish certain chemical processes, such as breaking down food and clotting blood. They're used throughout your body for many vital functions. Abnormal enzyme levels can indicate many different conditions.
Common enzymes tested include:
Here are the normal ranges for the enzyme listed above:
Many sexually transmitted diseases (STDs) can be diagnosed using a blood sample. These tests are often combined with urine samples or swabs of infected tissue for more accurate diagnoses.
The following STDs can be diagnosed with blood tests:
Blood tests aren't always accurate right after contracting an infection. For an HIV infection, for example, you may need to wait at least a month before a blood test can detect the virus.
Coagulation tests measure how well your blood clots and how long it takes for your blood to clot. Examples include the prothrombin time (PT) test and fibrinogen activity test.
Clotting is a crucial process that helps your stop bleeding after a cut or wound. But a clot in a vein or artery can be deadly, blocking blood flow to your brain, heart, or lungs and causing heart attack or strokes.
Coagulation test results vary based on your health and any underlying conditions that may affect clotting.
Results from this test can be used to diagnose:
The dehydroepiandrosterone (DHEA) hormone comes from your adrenal glands. This test measures whether it's too high or too low.
In men, DHEA helps develop traits like body hair growth, so low levels are considered abnormal. In women, high levels can cause typically male traits, like excess body hair, to develop, so low levels are normal.
Low levels in men are called DHEA deficiency, which can be caused by:
High levels in men or women can result from:
C-reactive protein (CRP) is made by your liver when tissues in your body are inflamed. High CRP levels indicate inflammation from a variety of causes, including:
The higher the level in your results, the higher your risk of heart disease:
These procedures are usually done at a laboratory or in a doctor's office and take a few minutes.
To perform a blood test, a nurse or technician:
The risks of routine blood tests are very low, but can include:
Blood tests offer an important snapshot of your overall health. They're also a good way to catch illness or disease early or see how well your body responds to treatments for various conditions.
Get routine blood tests done at least once a year. Talk to your doctor to learn if there are any other tests you may need to ensure your optimal health.