Which Blood Type May Raise Your Risk of Type 2 Diabetes?

Type 2 diabetes is among the most widespread health conditions in the United States. Roughly 1 in 8 Americans lives with diabetes, and about 90% to 95% of those cases are type 2. As with many medical conditions, both heredity and lifestyle contribute to its development. Some research suggests that people with type B blood could face a higher chance of type 2 diabetes, though the reason is not clear and further studies are needed to verify the connection.

Your blood group is determined by markers on the surface of your red blood cells. You inherit one marker from each parent, and together they form your blood type. The main blood groups are O, A, B, and AB, based on whether A or B markers are present. People with type O have neither marker, while those with type AB have both. Blood types are also labeled positive or negative depending on whether they carry the rhesus factor. In the United States, the most common blood type is O positive.

Type 2 diabetes is mainly driven by insulin resistance. Insulin is a hormone made by the pancreas that moves sugar from the blood into the liver, fat cells, and muscle cells. When insulin levels stay high over time, the body can become less responsive to it. As a result, blood sugar remains elevated for long periods, damaging cells and leading to complications such as nerve and blood vessel injury.

Does type B blood have a connection to type 2 diabetes?

No firm link between type B blood and type 2 diabetes has been proven. Some studies suggest that people with type B may be more likely to develop the condition, but the findings have not been consistent. Researchers also have not confirmed a clear biological explanation for the possible association.

In one study from 2021, researchers examined blood type data from 400 people with diabetes and 400 people without diabetes in Karachi, Pakistan. They found that type B blood was significantly associated with type 2 diabetes, while type O was negatively associated, meaning it appeared less likely among people with diabetes. Similarly, a study from India reported comparable results in a sample of 300 people.

A 2022 review of studies by researchers in Ethiopia also found that people with type B had a 30% higher risk of type 2 diabetes, while people with type O had an 8% lower risk than the general population across 6,870 participants in 26 studies. A 2023 meta-analysis reached different conclusions, reporting the lowest risk among people with type B and the highest risk among those with type AB. These studies, including the reviews, are still relatively small, and larger research is needed to determine whether a real link exists and what might explain it.

What other health conditions are associated with blood type?

While researchers are still studying whether blood type is a genetic risk factor for type 2 diabetes, stronger associations have already been identified between blood type and other health conditions. For example, type A blood may be tied to a higher risk of stroke. People with type O may have a lower risk of heart attack than those with other blood groups.

Type O has also been linked with infections such as mumps, tuberculosis, and cholera. People with type AB may have a greater risk of Salmonella, smallpox, and E. coli infections. Those with type A blood appear to have higher rates of smallpox, stomach cancer, and ovarian cancer. Type B has been associated with gonorrhea, streptococcal pneumonia, and Salmonella.

Regardless of your blood type, you can help lower your risk of type 2 diabetes by cutting back on refined sugar. One simple step is to swap sugary drinks such as soda for tea or water. You can also replace sugary desserts like cake or cookies with naturally sweet fruits such as bananas or apples.