Your blood type can actually mean a lot as a number of studies have correlated different blood groups with everything from risk of heart disease to infertility. While none of these studies are conclusive about cause and effect, the research does highlight the importance of knowing your type—A, B, AB, or O—and how it could affect your well-being.
Fertility: Type O reduces it
According to an Albert Einstein College of Medicine study, Women with blood type O were twice as likely to have blood levels of the hormone FSH (follicle stimulating hormone) high enough to indicate low ovarian reserve or a measure of fertility.
Researchers don’t know why, especially given the fact that type O blood is the most prevalent across the world. There is nothing to worry about though, age is a far more important risk factor for fertility problems.
Blood clots: Type AB, A, and B increases risk
Researchers from Denmark have studied how blood type interacts with a genetic predisposition for deep-vein thrombosis (DVT), or blood clots in the lower legs that can travel to the lungs and become life-threatening.
After analyzing data on about 66,000 people over more than 30 years, they found that those with type AB, A, or B had a 40 percent higher risk of DVT than people with type O, which is the most common type.
After further analysis to see which factors have the biggest impact on DVT risk on a population level, they found that an AB blood type contributed to about 20 percent of blood clots; genetic mutations accounted for 11 percent, being overweight accounted for 16 percent, and smoking accounted for 6 percent.
Heart disease: Type AB, B, and A all increase risk
Scientists from Harvard analyzed more than two decades of data on more than 77,000 people and found that those with AB blood had a 23 percent increased risk for heart disease compared to people with type O blood. Those with type B blood had an 11 percent higher risk and those with type A blood had 5 percent greater risk.
While the studies are inconclusive, researchers Researchers posit that type A blood is associated with LDL cholesterol and that type O blood, which is associated with reduced risk, may contain a chemical that boosts blood flow and prevents clots.
They however pointed out that lifestyle factors like weight, smoking, and diet, which, unlike blood type, are modifiable, have a much greater impact on heart disease.
Stomach cancer: Type A increases risk
People with blood group A had a 20 percent greater chance of developing gastric cancer compared to people with blood group O, according to a Swedish study from the Karolinska Institute. These people may also be more vulnerable to other stomach cancer risk factors such as cigarette and alcohol use.
Meanwhile, the same Swedish study found that those with type O blood had an increased risk for stomach ulcers; they may be more susceptible to the Helicobacter pylori bacteria that cause the stomach sores.
This has nothing to do with your “letter” blood type, or the type determined by the ABO grouping system. This has to do with the Rh factor, which determines whether your blood type is positive or negative.
This factor could cause complications in pregnant women if the baby’s Rh blood type is different from the mother’s. For instance, if the mother has a negative blood type and the baby has a positive one, the mother’s body can actually build up antibodies against the baby’s blood type. Luckily, this doesn’t affect the baby, but it could have a disastrous effect on future pregnancies.
The good news is that doctors can give pregnant women a shot early in their pregnancy that can prevent Rh-incompatibility problems.