Thousands of studies have examined how blood type influences various health parameters and longevity. However, experts have concluded that only one of these connections is truly convincing: individuals with the second blood group according to the AB0 system—specifically B+ and B−—are noticeably more prone to developing type 2 diabetes. The findings were published in the journal BMC Medicine.
The research was conducted as an umbrella review, meaning a meta-analysis of meta-analyses, which made it possible to examine 51 systematic reviews encompassing 270 associations between blood type and different diseases. Every link was evaluated for reliability, reproducibility, and the absence of systematic errors. As a result, all 270 associations except one failed to withstand stringent statistical scrutiny.
The authors of the study revealed the sole association that passed the test: carriers of blood group B had a 28% higher likelihood of developing type 2 diabetes compared to those with all other blood types. This figure is not exceptionally high—for instance, a sedentary lifestyle increases diabetes risk by 112%, and regular consumption of 50 grams of processed meat raises it by 37%. Yet, the discovered link is both reliable and statistically robust.
The reason behind this correlation remains unclear. One hypothesis suggests that the gut microbiome may be the source, as the composition of microorganisms in the intestines varies among people with different blood types. However, this area has yet to be thoroughly investigated.
About the Author
