Iron enters our bodies through the food we eat. But did you know that you could be eating a diet rich in iron and still not have enough iron in your body?
Having enough iron is a two-part relationship. You need to receive enough iron from your diet, but your body also has to receive, retain, and transfer the iron properly.
That’s where an Iron Binding Capacity Test comes in. This test helps your health care providers know whether and why you have an iron deficiency or overload, and if your body is receiving the iron from your diet.
Below, we’ll walk you through everything you need to know about TIBC tests—from what they are exactly to whether you should get one, what you can expect, how to prepare for the test, and how to interpret your results.
What is Iron Binding Capacity?
In our blood, we have plasma proteins called Transferrin that carry iron molecules around the body. Transferrin is like a tandem bike. Each transferrin molecule has two slots or seats, so it can only carry two iron molecules.
Transferrin’s fixed number of seats (two) allows health care providers to calculate our iron binding capacity. Your total iron binding capacity is the maximum amount of iron “seats” or slots available in a particular volume of blood. In other words, it is the maximum amount of iron that can bind to the transferrin molecules in a blood sample.
What is a TIBC Test?
A Total Iron Binding Capacity (or TIBC) test is a blood test that measures your blood’s ability to attach itself to iron and transport it throughout the body. The results of this test will help your health care provider assess your body’s ability to transport iron in your blood and help diagnose iron-decifiency or iron overload.
Now that you understand what iron binding capacity means and what a TIBC test is, let's look a bit closer at the topic. Next, we’ll explain who should take a TIBC test, exactly what to expect when getting the test, test risks, and how to interpret your results.
Who Should Take a Total Iron Binding Capacity Test?
If you’ve had a complete blood count (CBC) and your hemoglobin and hematocrit is low, your health care professional may suggest taking a TIBC test to investigate further.
Low hemoglobin levels often indicate that a person has anemia. While there are several kinds of anemia, iron-decifiency anemia is the most common type. Without enough iron in the body, we cannot make the hemoglobin we need. Similarly, low hematocrit levels could indicate iron-decifiency anemia. Low hemoglobin and hematocrit could, therefore, indicate a problem with iron levels.
You may need a TIBC test if you have too little iron (an iron deficiency), but it’s also helpful if you have too much iron (an iron overload). Either way, a TIBC test will provide helpful information and shine light on why your iron levels are too high or too low.
How is the Total Iron Binding Capacity Test Performed?
After your blood is drawn for the TIBC test, the tube is labeled with your information and your sample is sent to the lab. There, your sample may be processed to separate the plasma (a light yellow liquid portion of blood) from the blood cells.
Often, your blood will be analyzed with automated instruments. Once your results are generated by the automated instruments, a lab professional will make sure the instrument performed properly and will analyze the results. These results are then sent to your health practitioner. If the results indicate that a patient needs immediate care, the laboratory personnel will immediately alert the healthcare provider.
Are There Any Risks of TIBC Tests?
While TIBC tests don’t in and of themselves pose risks, blood tests in general may, in rare cases, result in the following symptoms or complications:
- Feeling lightheaded, dizziness, or fainting
- A light bruise, a hematoma or blood collection under the skin
- Excessive bleeding
- Infection at the puncture site
What Can the Results of a TIBC Test Tell You?
Your TIBC test results will help you and your health care provider know if your body has enough iron, is responding properly to iron, and is capable of carrying iron in the blood. Your health care provider can review your results, noting whether they’re in the normal range, are too high, or are too low. Most laboratories show that a normal range for adults is 250 to 450 micrograms per deciliter (mcg/dL).
With this information, they can better detect if there’s a problem and whether treatment is necessary. Some labs use different measurements or test different samples. If you’re interested in understanding these measurements more, talk to your provider and ask them any questions about your specific test results.
Higher TIBC Value May Mean Low Iron Levels
When your iron levels are low, your liver may produce more transferrin proteins in an attempt to collect more iron. A higher number or transferrin will increase your TIBC value.
TIBC is typically higher during pregnancy or if using oral contraceptives. Otherwise, if your TIBC value is above the normal range of 250 to 450 mcg/dL, it could indicate that there’s a low level of iron in your blood.
A Lower TIBC Value May Mean High Iron Levels
A lower-than-normal TIBC value typically indicates a high level or iron in your blood. Anemia (or a lack of enough healthy red blood cells in your body) may cause low TIBC results. Hemochromatosis, iron or lead poisoning, liver damage, or frequent blood transfusions can also cause high iron levels and low TIBC results.
The Importance of Iron and our Iron Binding Capacity
If you’ve felt exhausted recently, find yourself winded even though you’re in good shape, or struggle to climb a flight of stairs, you might be lacking iron. And you’re not alone. According to the World Health Organization (WHO), low iron is the most common nutritional deficiency in the world.
Our body’s growth and development depends on iron. This essential mineral is a critical player in the production of our red blood cells, which carry oxigen around the body. Learning more about your body’s relationship with iron with a Total Iron Binding Capacity test might be a helpful option for you.
At Active Iron, we’re working hard to shrink the astounding number of people lacking enough iron. We’ve created iron capsules that are clinically proven to have two-times the absorption compared to standard supplements. Sample our supplement and see how much better you feel when you provide your body with enough iron.