Review Links Blood Type B to Higher Type 2 Diabetes Risk
People with blood type B face a 28 percent higher risk of developing type 2 diabetes compared to those with non-B blood groups, according to an umbrella review published in BMC Medicine. The finding emerges from a 2024 synthesis led by epidemiologist Fang-Hua Liu of Shengjing Hospital of China Medical University.
Key Clinical Takeaways:
- An umbrella review of 51 systematic reviews evaluated 270 associations between blood types and health outcomes.
- Only the link between blood type B and type 2 diabetes survived rigorous statistical stress tests to meet the highest standard of evidence.
- The 28 percent increase in risk remains far smaller than lifestyle factors such as a sedentary lifestyle, which increases risk by 112 percent.
The Umbrella Review Filtering 270 Health Outcomes
Liu and colleagues searched PubMed, Web of Science, Embase, Scopus, Cochrane Library, and regional databases through February 16, 2024. Their goal was to evaluate claims that subtle differences in red blood cells create vulnerabilities to specific diseases. Human blood relies on antigens and Rhesus factors to categorize types, with O-type blood carrying no A or B antigens, while A, B, and AB types possess sugar molecules capable of triggering immune responses.
The research team subjected 270 reported links between blood groups and human health outcomes to statistical stress tests. They examined study consistency, dataset sizes, and signs of bias like small-study effects. Most associations failed these checks.
“Numerous systematic reviews with meta-analyses have been published, which explored correlations between ABO and Rhesus blood groups with various health outcomes,” wrote a team led by epidemiologist Fang-Hua Liu of Shengjing Hospital of China Medical University. “However, to date, the association between these blood groups and human health outcomes remains controversial. The current umbrella review included 51 systematic reviews with meta-analysis articles with 270 associations.”
After recalculating each association, the team identified convincing evidence for only one relationship: blood group B and type 2 diabetes mellitus risk.
Comparing Blood Type Risk Against Modifiable Factors
The association between blood type B and type 2 diabetes is real, but modest. A 28 percent elevation in risk sits well below the thresholds established by behavioral and metabolic factors.
Consuming 50 grams of processed meat daily raises type 2 diabetes risk by 37 percent. A sedentary lifestyle drives that risk up by 112 percent. Excess body weight remains one of the strongest risk factors known, rendering blood type a minor component of an individual’s overall risk profile.
The published research did not investigate the biological mechanisms driving the correlation between blood group B and metabolic disease. While a separate 2025 study points toward potential involvement of the gut microbiome, scientists emphasize that diet, physical activity levels, and body weight dictate diabetes vulnerability far more than surface antigens on red blood cells.
Disclaimer: The information provided in this article is for educational and scientific communication purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider regarding any medical condition, diagnosis, or treatment plan.