Nov. 18, 2024—You probably know that blood type matters when it comes to receiving a blood transfusion. People who receive blood need to get it from a compatible donor. But did you also know that your blood type might make you more or less susceptible to certain health risks?
What is a blood type?
Your blood type is something you inherit from your parents. It's determined by the presence or absence of molecules called antigens on the surface of blood cells. The four main blood types are A, B, O and AB.
Some research suggests that a person's risk for certain conditions may depend in part on their blood type. These conditions include:
Blood clots. People with blood types A and B may be more likely to develop blood clots in the lungs or the deep veins of the legs.
Heart attacks and strokes. Both may be more common in people with A and B blood types, as well as in those with non-O blood types (A, B or AB) who have had COVID-19.
COVID-19. People with type O blood (about 38% of the U.S. population) may be more resistant to COVID-19 infections than those with type A blood, the American Society of Hematology reports.
Norovirus. One study found that people with type O blood may be more prone to norovirus infections, a foodborne illness that causes vomiting and diarrhea.
Certain cancers. Some types of cancer may be more common among people with certain blood types. For example, some evidence shows that stomach cancer is diagnosed more often in people with type A blood, whereas pancreatic cancer may be more common in those with A, AB or B blood types.
Rh incompatibility. Most people are Rh-positive, meaning they have an Rh-factor protein in their red blood cells. Rh incompatibility can occur when an Rh-positive baby is born to an Rh-negative mother. If the baby's blood is passed to the mother, her body will attack the baby's red blood cells.
Keep your blood type and your risk in perspective
To be clear, just because you have a certain blood type doesn't mean you will get a disease or be protected from it. Your blood type may be only one small part of your overall risk.
You can't change your blood type. But you can focus on risk factors you can change. Talk to your doctor about your risk factors for conditions like these—and what you can do to reduce them. And stay up-to-date on vaccines to help protect against diseases like COVID-19.
Curious about your blood type?
Donating blood is one way to find out what blood type you have. Plus, your donation will do a lot of good. Learn more about donating blood.
Sources
- AARP. "What Your Blood Type Says About Your Health." https://www.aarp.org/health/healthy-living/info-2023/how-your-blood-type-affects-your-health.html.
- American Academy of Family Physicians. "Rh Incompatibility." https://familydoctor.org/rh-incompatibility.
- American Heart Association. "COVID-19 May Increase Heart Attack and Stroke Risk for Years." https://www.heart.org/en/news/2024/10/09/covid-19-may-increase-heart-attack-and-stroke-risk-for-years.
- American Heart Association. "What's Blood Type Got to Do With Clot Risk?" https://www.heart.org/en/news/2020/01/23/whats-blood-type-got-to-do-with-clot-risk.
- American Red Cross. "Know Your Blood Type." https://www.redcrossblood.org/donate-blood/blood-types/know-your-blood-type.html.
- American Society of Hematology. "Study Uncovers Direct Link Between Blood Group A and a Higher Risk for COVID-19 Infection." https://www.hematology.org/newsroom/press-releases/2023/study-uncovers-direct-link-between-blood-group-a-and-a-higher-risk-for-covid-19-infection.