Blood tests are a common component of visits to your doctor's office. Equally common is the confusion that comes with the results. There are a lot of abbreviates and a wide range of numbers. What exactly are these tests checking for and what can they indicate?
As a fitness enthusiast, you're used to assessing the health of your body through its ability to perform during workouts. And while reading blood profiles can be a lot to take in, but they're just another way to analyze your body's health. Get to know the basics of common blood tests so you can truly understand how your body is functioning.
A complete blood count, or CBC, is the most common blood test requested. This is the test your doctor will usually order for your annual exam. It provides an overview of your body's health and how well the basics are functioning.
There is a normal range for each component of a CBC (and other blood tests) that indicates overall good health, and when a measurement falls outside that range it can be a sign that something unusual is going on within your body. The components a CBC analyzes include the following:
White blood cells
Red blood cells
These are the cells responsible for fighting infection in your body. This measurement counts the number of WBCs in a volume a blood, such as 6 billion cells per liter. A high WBC count may result from inflammation, an allergic reaction, or an infection. A low WBC count could signify cancer, an autoimmune disease, or a side effect from a medication.
RBCs transport oxygen throughout your body. Like the WBC count, the RBC count measures the number of red blood cells in a volume of blood. For example, your blood profile may show your RBC count as 5 trillion cells per liter. High counts can indicate issues such as dehydration or heart or kidney disease. Low counts may also indicate kidney disease, as well as a nutritional deficiency or anemia.
Hemoglobin is part of the red blood cell; more specifically, it is the protein in the cells that carries the oxygen. The results typically display as grams per deciliter, such as 14.5 grams per deciliter. Blood tests include hemoglobin levels to gauge if your tissues are receiving enough oxygen. Additionally, lower than average measurements are another indication of anemia.
While the RBC count measured the number of RBC cells in a volume of blood; hematocrit measures the ratio of those cells to the whole volume. For example, if the Hct measurement in your blood profile displays 45%, then 45% of your blood is red blood cells. This test helps determine the optimal number of red blood cells and can be another indicator of anemia.
Platelets are vital to blood clotting and measured in comparison to a volume of blood, such as 300,000 platelets per microliter of blood. Abnormal amounts can affect blood clotting—too much or too little—and generally require additional tests to determine to the cause of variation.
A lipid profile, also called a lipid panel, assesses the fats in your body. Like the CBC, a lipid profile is a common piece of an annual exam. This test specifically measures the cholesterol and triglycerides in your blood and can help assess your risk for heart disease.
Key measurements in a lipid profile include:
High-density lipoprotein cholesterol
Low-density lipoprotein cholesterol
A certain amount of cholesterol is essential for normal body functions. Cholesterol helps to create certain hormones, form bile acids that support nutrient absorption, and form cell membranes. High levels of total cholesterol indicate a higher risk for heart disease.
This is the "good" cholesterol and protects against heart disease. HDL carries excess cholesterol to the liver for disposal.
LDL, the "bad" cholesterol, is the portion that sticks to blood vessel walls, causing hardening of the arteries, and heart disease. However, a certain amount of LDL cholesterol is still needed for cell repair.
While triglycerides provide important energy to the body, too many can be detrimental to your health. Excess amounts can turn to fat and increase your risk for heart disease.
A metabolic panel is another standard for your annual exam. The CMP is a series of blood tests that measures different chemicals in your blood. To measure some of these blood chemicals appropriately, your doctor will likely ask you to fast 8-12 hours prior to testing. A CMP will provide insights on your:
You blood profile will show the waste levels in your blood for blood urea nitrogen (BUN) and creatinine. Abnormal levels of either of these elements can indicate the presence of kidney disease, though high BUN levels can also be an effect of high-protein diets.
A healthy liver creates the enzymes ALP, ALT, and AST, and disposes of bilirubin, a component of bile. These elements help your body process food and remove harmful substances. Irregular measurements can be a sign of liver disease or liver damage.
Also known as blood sugar, glucose is an important source of energy. This is a key piece of your blood test as high levels can indicate a risk for diabetes and low levels indicate potential hypoglycemia.
Normal electrolyte levels help your body balance fluids, control your heartbeat, and control how your muscles and brain work. Variances can be an indication of dehydration, kidney disease, or heart disease. Common electrolytes tested include chloride, potassium, and sodium.
Proteins are important for the healthy creation of not just muscles but also blood, bones, and organs. The main protein tested is albumin, a product of your liver. Thus, low protein levels can indicate liver problems as well as kidney disease or nutritional problems.
Each of these blood tests provide deeper insight to the inner workings of your body. Now that you know what each test is checking, you can begin to find way to improve and maintain healthy measurements. And remember, averages can vary depending on age, gender, fitness, and other factors, so talk with your doctor about the normal range that indicates healthy levels for you and your lifestyle. The more you know about your body to more you can work to protect it and live a healthy life.
If you're interested in learning more about setting your body up for success, check out the ISSA's Fitness Nutrition Certification—healthy nutrition supports a healthy body.