After many years of lacking knowledge about my blood type, I have finally found out what my blood type actually is. To my surprise I discovered that I have a rare blood type in the overall global population: AB- blood. Statistics show that only 3.4% of the world’s population have AB+ blood and only .6% have AB- blood. This new-found information about myself made me wonder whether my blood type could impact me and what were its beneficial or detrimental effects on my health.
Some very different studies have found interesting differences between blood types when it came to developing certain diseases or have neurological problems with age. A study published by Kristine Alexander, Ph.D., postdoctoral fellow in medicine and Mary Cushman, M.D., M.Sc., professor of medicine at the University of Vermont College of Medicine, revealed that people with AB blood had an 82 percent higher chance of developing neurological problems like dementia and memory loss. The sample size of the study was relatively big, consisting of 30,000 individuals who were followed for 3.4 years. They relied on information collected twice a year through phone surveys that measured the cognitive ability of participants in the study. They focused on 494 individuals whose skills regarding memory, learning and other cognitive functions were severely or moderately reduced in that period of time. After taking into account possible third variables like race, sex and geography, they concluded that the individuals with AB blood in the study were the ones with prevalent negative cognitive results as the years passed.
Of course, there is room for chance in the study and it could’ve been a false positive/fluke. However, the sample size itself was remarkably big and so it leaves less room for the possibility of coincidence. We don’t know if these surveys were actually reliable sources of data on these individuals but we can assume that they were since many scientific websites spoke about this same study and summarized it effectively. Furthermore, there could always be the presence of third variables in the study even when taking into account factors like gender, race and geography. One example of a third confounding variable could be the employment of each individual and how their respective tasks in their jobs could affect their cognitive processes. However, the results were extremely high when it came to the percentage of people with AB blood and cognitive dysfunctions so we can assume there might be something going on. Scientists predict that the mechanism behind this increase in the rate of gradual cognitive impairments in AB blood is the presence of more factor VIII in this blood than any other, a protein that is also related to cognitive impairment.
Additionally, another study was conducted to identify certain blood types and their relationships with other diseases. In this respective study, scientist Arash Etemadi and his group accompanied a sample size of 50,045 70 year-old individuals during the course of 2004-2008 to see if individuals with certain blood types had higher chances for vascular disease, higher mortality rates and certain types of cancer. What they found is that people with non-O blood types had a 55% greater chance of developing gastric cancer and 15% were more likely to die from cardiovascular disease then O blood types. They also found that type A blood types have higher chances of having high cholesterol than the other blood types.
This study was controlled randomized study and it took into account variables such as age, gender, socioeconomic status, ethnicity, place of residence, education and opium use. There is no chance of reverse causation in this study, since a certain disease cannot cause blood type but there are chances of third variable being the real culprits in disease. For example, maybe many individuals in the A and B blood types have a propensity to eat certain foods that increase their chances of developing gastric cancer. The sample size was big enough to reduce the likeliness of chance in this study, but there is still a possibility that it was a fluke and so other studies should be conducted to evaluate whether the results were in fact not a fluke.
Overall it seems that O blood types have the advantage when it comes to not developing certain diseases in comparison to other A, B and AB blood types. Yay for the Os! This is good news since the majority of the world’s population is comprised of individuals with the O blood type. However, scientists tell individuals with non-O blood not to worry about these results since there are other factors that may decrease someone’s likelihood of developing certain diseases like frequent exercise, a healthy diet and abstention from negative habits like smoking and drinking.
This is interesting! I wonder why people with O blood would have slightly healthier bodies than other types. I had never thought that something like that mattered whatsoever. I am lucky that I have O blood type, but why do O blood types have lesser chances of developing some cancers/neurological problems? It was hard to find a mechanism- scientists most likely don’t have one yet. But one theory I have based off the source I looked that is that each blood type is distinguished by what antigens they have on the surface of their red blood cells. Each antigen must be different at protecting against certain diseases- this may be why people with O blood are the most common, even though the O type of blood is recessive. For the blood type to so widespread, it must help those that have it survive at least a little better than those who don’t have it (at least in the past!).
Reading this entry was kind of eye-opening for me, since I am an A+ blood type. I have always had a high cholesterol level, even though I am a very healthy and fit kid. My doctors have told me I probably got it from my parents, but now I have reason to believe it is my blood. By any chance, do you know if scientists looked into the transfusion side of the blood types? For example, I know that people with AB blood can take transfusions from any other blood type, but cannot donate to any other type, and vice-versa for O blood types. This could lead to the saving of lives of many AB blood types, potentially throwing off the data.