Your blood type is more than just a label; it’s important health information. Knowing your blood type is important for when you need a transfusion or when you want to donate blood, but did you know it can reveal even more about your health, including your risk for certain diseases? Take control of your health and learn what clues your blood type might reveal.
What are the most common blood types?
Overall there are eight major blood types:
- O+ and O-
- A+ and A-
- B+ and B-
- AB+ and AB-
Like many of your features, such as eye color, your blood type is inherited from your parents. And just like other genetic traits, certain blood types are more common than others.
For instance, Type O positive blood is the most common; nearly 37% of the U.S. population has it. On the other hand, only 7% of the population has Type O negative blood. Blood donation organizations seek Type O negative blood because it is considered the “universal red cell donor” blood type. This means anyone—no matter their blood type—can receive Type O negative blood in emergency, often life-saving transfusions.
What is Rh factor? What does it affect?
Rh factor, or rhesus factor, is an inherited protein that helps determine your blood type. If your blood type is Rh-positive (O+, A+, B+, AB+), your red blood cells carry this protein; if your type is Rh-negative (O-, A-, B-, AB-), your cells do not carry it.
Rh factor determines the compatibility of two people’s blood, which makes knowing your Rh factor important during pregnancy and for blood transfusions.
People with Rh-negative blood types can have serious reactions to Rh-positive blood types because their immune systems view the Rh-positive blood as a threat and attack it. This immune response can occur when someone accidentally receives incompatible blood during a transfusion or when an Rh-negative person is pregnant with an Rh-positive baby. In pregnancy, Rh incompatibility can result in harm to the developing baby. Fortunately, these pregnancy complications can be prevented with injections administered by a healthcare provider and are a part of routine prenatal care if needed.
The connection between blood type and cardiovascular disease
People with blood types A, B or AB are at a slightly higher risk of developing heart disease than those with Type O. This is because their blood contains antigens that can make it more likely for blood clots to form. While the increased risk of heart attack is small (8%), the risk of blood clotting and deep vein thrombosis is much higher (over 50%), according to one study.
Regardless of your blood type, there are ways to reduce your risk of heart disease. You can start by eating a well-balanced, heart-healthy diet that includes plenty of fruits, vegetables and whole grains, as well as limited amounts of saturated and trans fats, cholesterol and sodium. Exercising regularly and maintaining a healthy weight can also reduce your risk.
The connection between blood type and cancer
People with certain blood types may be at an increased risk of developing certain cancers.
Studies have shown that people with Type A blood have a slightly higher chance of developing stomach cancer than people with Type O blood. Similarly, a study revealed that while the overall risk is relatively low, individuals with Type O blood were less likely to develop pancreatic cancer than people with A, B, or AB blood types.
People with A, B, or AB blood types may also have a higher risk for lung, breast, colorectal, prostate, liver and cervical cancers. Researchers are still trying to understand exactly how blood type and these cancers are connected.
If you have a blood type that is associated with an increased risk of cancer, it is important to be aware of the signs and symptoms of the disease so that you can get early diagnosis and treatment. You should also talk to your health care provider about ways to reduce your risk of cancer, such as eating a healthy diet, exercising regularly and not smoking.
The connection between blood type and stroke
About 4 out of 5 strokes are preventable, and there are genetic factors that can put you at an increased risk. People with Type A blood have a higher risk for stroke than those with Type O blood. A recent study found that patients who had an early stroke (before age 60) were more likely to have Type A blood, while those with Type O blood had a 12% lower risk of having a stroke.
If you have a blood type associated with an increased risk of stroke, it is important to talk to your doctor about the signs and symptoms of stroke. Regardless of your blood type, lifestyle behaviors including eating a healthy diet, getting regular exercise, reducing alcohol consumption and not smoking could help reduce your risk.
Curious about your blood type? Go test yourself!
Labcorp OnDemand offers a robust suite of wellness and screening tests that help you and your provider get a better overall picture of your health. Our Blood Type Test is a quick and easy way to discover your blood type. The test can also help you learn more about your overall health and how your blood type may affect your risk for certain diseases.
Receive results in 1-2 days from when our lab receives your sample and start taking more control over your health today.
