What Your Blood Type Reveals About You, According To Science

Knowing your blood type helps with more than just blood transfusions. Researchers have discovered that blood type corresponds with a host of health conditions, such as fertility, heart disease, and dementia.

It’s a good idea to find out whether you are type A, B, AB, or O. It may determine whether mosquitoes are attracted to your blood. You could also have higher chances of certain cancers, or you could safely accept any blood type transfusion. If you’re ready to know what your blood type reveals about you, keep reading.

Mosquitoes Favor Certain Types Of Blood

Several mosquitoes cling to a window.
Getty Images
Getty Images

Some people need more bug spray than others. Research has found that mosquitoes favor certain blood types. In 2004, research in the Journal of Medical Entomology concluded that people with blood type O receive the most mosquito bites. Blood type A is the next favorite.

Why do mosquitoes prefer certain blood types? According to Dr. Baumann-Blackmore, they’re attracted to chemicals in sweat. Certain blood types produce more substances such as ammonia and lactic acid, which mosquitoes like. If you have blood types A or O, don’t leave the house without some bug spray.

Non-O Blood Types Have A Greater Risk Of Heart Disease

A man clutches his chest in pain while on a hike.
BSIP/Universal Images Group via Getty Images
BSIP/Universal Images Group via Getty Images

According to the American Heart Association, certain blood types have a higher risk of heart conditions. A study in Arteriosclerosis, Thrombosis, and Vascular Biology said that O bloods have a lower risk, while AB bloods have higher risks. AB types have an 8% greater risk of heart attacks and a 10% increased heart failure chance.

Penn Medicine explains that non-O bloods contain a protein called the von Willebrand factor. This slightly raises the risk of clotting and high cholesterol. However, the chances are still slim, and you can remain healthy with a proper diet and exercise routine.

Blood Can Affect Your Chances Of Getting The Stomach Flu

A woman on the couch clutches her stomach while looking at medication.
BSIP/UIG Via Getty Images
BSIP/UIG Via Getty Images

Norovirus, better known as the stomach flu, infects 200 million people every year. Surprisingly, your blood type might influence your chances of getting it. According to Science Times, the norovirus needs to attach to H1, a type of blood antigen. If your blood doesn’t produce the H1-antigen, you may have some immunity to the stomach flu.

AB blood types tend to be more susceptible to norovirus than O blood types. However, this can vary among individuals. The norovirus consistently changes, and immunity only lasts for around six months. Even if you are less susceptible, you could still get the stomach flu once in a blue moon.

Certain Blood Types Are In More Danger Of Dementia

A woman with Alzheimer's looks through old photos.
Mario Tama/Getty Images
Mario Tama/Getty Images

In 2014, research in the journal Neurology discovered that certain blood types have a higher risk of cognitive impairment. AB blood types were 82% more likely to have cognitive impairment, which can lead to dementia. O types have a lower chance.

Researchers suggest that this could have to do with heart disease. AB types also have a greater chance of high cholesterol, high blood pressure, and diabetes. Dr. Mary Cushman says that these conditions are closely related, and people with diabetes or stroke are more likely to develop dementia.

Some Blood Types Are More Prone To Food Allergies

A nutrition label lists common allergens.
SEBASTIEN BOZON/AFP via Getty Images
Tamir Kalifa for The Boston Globe via Getty Images

Studies have found that food allergies might be influenced by blood. In 2007, research in the Journal of Nutritional & Environmental Medicine compared the likelihood of specific food allergies to blood type. Overall, people with negative blood types are more susceptible to food allergies.

According to the study, people with type O blood are more likely to react to gluten, nightshades, eggs, and dairy. Those with AB blood are susceptible to nuts, seafood, eggs, dairy, and gluten allergies. Of course, allergies are also genetic just as blood types are. There is no guarantee that you will have an allergy solely because of your blood type.

All Non-O Bloods Risk Pancreatic Cancer

A drawing shows the pancreas and bile duct.
Universal Images Group via Getty Images
Universal Images Group via Getty Images

Pancreatic cancer is one of the most fatal cancers. A study in the Journal of the National Cancer Institute found that non-O blood types–A, B, and AB–have a higher risk of developing pancreatic cancer.

Of these, B blood types have a greater risk. A has a 32% chance, B has a 51% risk, and AB has a 72% chance. The study’s lead author, Dr. Brian Wolpin, says that scientists don’t yet understand what heightens the pancreatic cancer risk.

AB Blood Clots More Often

A doctor tests a donor's blood.
200degrees/Pixabay
FRED DUFOUR/AFP via Getty Images

Depending on your blood type, you could have a higher risk of blood clotting or hemorrhage. The American Heart Association reports that AB blood types are more likely to clot. Chances of deep vein thrombosis, or clotting in the leg, raise by 47%. Pulmonary embolism, or clotting near the lungs, raises by 51%.

AB bloods have a protein that slightly increases the risks of clotting. On the other hand, O blood types are more likely to hemorrhage. A Japanese study in Critical Care found that O bloods have a 28% higher risk of hemorrhaging.

Blood Can Affect Diabetes Risk

A woman with diabetes measures her blood sugar.
Gideon Mendel/Corbis via Getty Images
Romulo Yanes/Conde Nast via Getty Images

Many people know that diet and exercise habits affect the risk of diabetes. But blood type could also contribute, if only slightly. French researchers from the Gustave Roussy Institute discovered that women with B positive blood have the highest chances of developing diabetes.

According to the journal Diabetologia, people with B-positive blood have a 35% greater risk of diabetes. The percentage changes to 10% with type A blood, 17% with AB blood, and 21% with B-negative blood. People with O type blood have the lowest chance of diabetes. Remember, though, that blood type is not a diabetes-sentence.

Type A Bloods Are More Prone To Stomach Cancer

A woman clutches her stomach in pain.
BSIP/UIG Via Getty Images
BSIP/UIG Via Getty Images

Unfortunately, people with type A blood are more likely to get gastric cancer. In 2012, a study in the International Journal of Molecular Sciences found that A-type blood is susceptible to H. pylori. This pathogen creates inflammation and is one of the more prominent risk factors for stomach cancer.

Further research in BMC Cancer asserted that both type A and type AB bloods are prone to gastric cancer. The study suggested that type A genotypes are more prone to H. pylori than O or B blood types.

The Rarest And Most Common Blood Types

A woman holds up a card showing her blood type, O positive.
Scott Olson/Getty Images
Scott Olson/Getty Images

Since blood types are genetic, how common they depend on ethnicity. However, the rarest blood type overall is AB-negative. Less than 1% of the American population has AB-negative, while 4% has AB-positive blood.

Worldwide, the most common type of blood type is O-positive. Between 37% and 53% of the population has O-positive blood, depending on the country. O-negative blood, the universal donor, is far rarer. People with O-negative blood make up between 1% and 8% of the overall population. Blood types A and B are somewhere in the middle.

O Negative Is The Universal Donor

A diagram lists all of the types of blood.
BSIP/Universal Images Group via Getty Images
BSIP/Universal Images Group via Getty Images

According to the San Diego Blood Bank, one blood type is a universal donor. O negative only exists in 8% of the population, but it is required for 13% of hospital blood requests. The reason is because O type does not attract antibodies from other blood types.

Lorne Laboratories explains that O negative blood lacks antigens. Usually, antigens prompt the immune system to attack new blood entering the system. Since O negative blood doesn’t get attacked, it is safe to infuse even in newborn babies. This is why the demand for O negative blood is so high.

AB Blood Is The Universal Recipient

A blood bank carries AB blood.
FRED DUFOUR/AFP via Getty Images
FRED DUFOUR/AFP via Getty Images

Most blood types can only accept certain types of donated blood. The American Society of Hematology explains that using incompatible blood types can cause allergic reactions, infections, or anemia. But one is the universal recupient: type AB positive.

People with type AB positive blood make up only 3% of the population. They can receive red blood cells from every other blood type. However, people with AB negative blood are universal plasma donors. People who need plasma can obtain it from AB negative, regardless of their blood type.

People With Type O Blood Are Less Prone To Malaria

Two Asian tiger mosquitoes feed on a human.
Smith Collection/Gado/Getty Images
Smith Collection/Gado/Getty Images

People with type O blood have greater protection from severe or fatal malaria than other blood types. In 2015, Scandinavian scientists tried to find out why. They believe that type O blood was in countries that eventually developed immunity to malaria, such as Nigeria.

Malaria causes a phenomenon called a rosette. Rosettes form when an infected red blood cell connects with a healthy red blood cell. According to Nature Medicine, O-type blood has antibodies that interfere with rosettes. Malaria cannot infect the body as quickly if you have type O blood.

Certain Blood Types May Require Different Diets

Students pull carrot and celery slices from a plate.
Nikos Pekiaridis/SOPA Images/LightRocket via Getty Images
FRED DUFOUR/AFP via Getty Images

Naturopath Peter J. D’Adamo claims that peoples’ diets may rely on their blood types. His theory, called the Blood Type Diet, suggests that certain bloods need to avoid and embrace different foods.

According to D’Adamo, O blood types benefit from a high-protein diet that is light on grains and dairy. A blood types may prefer meat-free diets, and B bloods should avoid many nuts, beans, and grains. AB bloods should focus on seafood and tofu and avoid caffeine. The downside of the Blood Type Diet is that it can be restrictive and inflexible.

People With AB Blood Are More Likely To Lose Their Memory

A businessman presses his fingers against his temple while sitting as his desk.
BSIP/Universal Images Group via Getty Images
BSIP/Universal Images Group via Getty Images

AB is the rarest blood type, consisting of only 4% of Americans. However, research from the American Academy of Neurology found that AB blood types have a higher risk of memory problems. In fact, people with AB blood are 82% more likely to experience cognitive decline.

AB blood also raises the risk of heart attack and stroke, closely related to cognitive impairment. Factor VIII, a blood protein that makes blood clot, may also heighten the risk of dementia. However, researchers still need more evidence to determine why AB types suffer from memory loss.

Does Blood Type Determine Your Personality?

Silhouettes of people stand in front of different colors.
BSIP/Universal Images Group via Getty Images
BSIP/Universal Images Group via Getty Images

In Japan and South Korea, many people believe that blood influences your personality, similar to zodiac signs. This is called the blood type personality theory. According to the scientific journal Personality and Individual Differences, research has yet to support this theory, calling studies about it “scanty” and “conflicting.”

People with blood type A are supposedly empathetic and good listeners. B type people are natural leaders, and AB people are independent, rational thinkers. People with the blood type O are practical and motivated. But that’s just an overview; the full theory is far more detailed.

Blood Type May Influence Fertility

A woman holds a pregnancy test.
Universal Images Group via Getty Images
Universal Images Group via Getty Images

In 2010, a study suggested that a woman’s blood type may affect fertility. Researchers from the Albert Einstein College of Medicine and Yale University measured the follicle-stimulating hormone (FSH) in blood. High FSH levels make it harder to conceive.

Women with type O blood had the most FSH levels, which meant that they often had lower egg count and quality. Women with type AB blood had fewer FSH. In short, O-type blood inhibits fertility, while AB-type blood improves it. Between types A and B, people with type A had better luck with fertility.

Negative Blood Types Can Prompt Negative Mental Health

A woman hugs her knees in despair.
Maciej Luczniewski/NurPhoto via Getty Images
BSIP/Universal Images Group via Getty Images

Believe it or not, blood type could influence brain health. In 2015, a study in PLoS One discovered that blood type could raise or lower your risk of mental illness. People with negative blood types have a higher risk of anxiety disorders, antisocial disorders, and attention deficits.

According to scientists from the University of Vermont, people with type O blood were more likely to get depression, anxiety, and attention-deficit disorder (ADD). People with A-type blood have a risk of obsessive-compulsive disorder and ADD. Children with B type have a greater chance of ADD.

Blood’s Rh Factor Can Complicate Pregnancy

A pregnant woman sips from a mug while standing at a desk.
FRANCK FIFE/AFP via Getty Images
Universal Images Group via Getty Images

Rh is a protein in red blood cells, and it determines whether your blood is positive or negative. Rh factors are often inherited. However, a problem arises when the mother has a negative Rh, and the fetus develops a positive Rh. The complication is called Rh incompatibility.

When the mother’s body detects a different blood type, it may create antibodies to attack the fetus. It could cause anemia in the fetus. According to the American College of Obstetricians and Gynecologists, there are treatments for Rh incompatibility that help both the mother and fetus.

Sugar Determines Your Blood Type

An illustration shows red blood cells.
Clker-Free-Vector-Images/Pixabay
Clker-Free-Vector-Images/Pixabay

Blood type is determined by antigens, a protein that lies on top of red blood cells. According to the Stanford School of Medicine, antigens are chains of sugar. The sugars they produce are called A sugar, B, sugar, and O sugar. Oddly enough, the actual function of these antigens is not known.

Blood Groups and Red Cell Antigens says that antigens seem to have no purpose. If you remove them from the blood, your health will not suffer. It is possible that these antigens used to have a purpose but stopped operating through evolution.