Blood Type and Diabetes Risk: What Researchers Found
It seems that your blood type could influence your diabetes risk, according to recent research. A review published in 2024 indicates that individuals with blood type B—whether positive or negative—may have a slightly elevated chance of developing type 2 diabetes compared to those with non-B blood types.
So, how much higher is the risk? On average, it appears to be about 28 percent. Now, that number might not sound particularly alarming at first glance, but it could become significant when combined with other risk factors.
A research team led by epidemiologist Fang-Hua Liu from Shengjing Hospital noted that while numerous systematic reviews have looked into the connections between blood types and various health outcomes, the debate around these associations is still ongoing. Their umbrella review analyzed 51 systematic reviews along with meta-analysis articles detailing 270 different connections.
They recalculated each of these associations and concluded that there was only one clear finding connecting blood type B to an increased risk of type 2 diabetes compared to non-B blood groups.
Human blood falls into eight primary categories, influenced by the sugars and proteins on red blood cells. Blood types A, B, and AB involve antigens—sugar molecules that can incite an immune response—while type O lacks these antigens. Additionally, Rhesus (Rh) factors contribute to blood compatibility and determine whether a type is positive or negative.
Earlier studies hinted that these slight variations in blood cell makeup might be tied to greater susceptibility to certain illnesses. Liu and their team set out to methodically assess the connections between blood types and a variety of health outcomes.
A systematic review consolidates and analyzes published research on a topic, while an umbrella review brings together these systematic reviews, creating a broader perspective of the findings. You might think of individual studies as trees; a systematic review as observing a small grove, and an umbrella review as surveying an entire forest from above.
The research team systematically searched databases to pinpoint systematic reviews that examined relationships between blood types and diverse health outcomes. They rigorously evaluated the 270 reported links for robustness, questioning the strength of the evidence and the integrity of the datasets involved.
They also looked for biases, such as smaller studies perhaps overstating effects or exhibiting an unusual number of positive results. A crucial part of their analysis involved considering whether the identified associations would likely hold true in future studies, and many of the links failed these assessments.
Ultimately, only the connection between blood type B and type 2 diabetes met their high standard for evidence. This suggests a genuine, albeit modest, relationship—28 percent higher risk compared to the baseline, which is notably less concerning than risks brought on by factors like diet and lifestyle.
For instance, consuming just 50 grams of processed meat daily boosts the risk of type 2 diabetes by 37 percent, while a lack of physical activity can increase risk by a staggering 112 percent. Being overweight is also among the most significant risk factors identified.
The researchers didn’t delve into what might be causing this increased risk, though a study from 2025 hinted that the gut microbiome could play a role, requiring further investigation.
These findings do establish a meaningful link between blood type and type 2 diabetes—something people might want to consider regarding their own health risks. Nevertheless, it’s important to remember that blood type isn’t the sole factor affecting diabetes risk. Factors like diet, exercise, and weight carry much more weight in the grand scheme of health.
The research appeared in BMC Medicine.
