According to webmd.com, here’s How Your Blood Type Can Affect Your Health
Stomach Cancer
A, AB, and B blood types are more at risk than type Os. Specifically, people with type A blood are more likely to get stomach cancer. Researchers think this might be because H. pylori infection is more common in people with type A blood. That’s a bacteria that’s usually found in the stomach. It can cause inflammation and ulcers.

Ulcers
Peptic ulcers — painful open sores that crop up in the lining of your stomach or upper intestine — seem to happen more often with blood type O.

Blood Clots

Venous thromboembolism (VTE) is when your blood clots in a deep vein, like the ones in your legs. These clots sometimes move to your lungs. Research shows that people with type A, B, or AB blood are at a higher risk of VTE.

Stroke
Your risk for a stroke goes up if you have blood type AB. Doctors think that’s because it’s more likely to clot than other types.

Diabetes
Type 2 diabetes seems to happen more often in people with blood types A and B. Experts aren’t sure why. More research is needed.

Heart Disease
There’s good news for O blood types. Research shows your risk of coronary heart disease tends to be lower. Experts aren’t sure why. Some think it might be because other types are more likely to have higher cholesterol and higher amounts of a protein that’s linked to clotting.

Stress
Stress boosts your body’s level of cortisol, the stress hormone. People with type A blood tend to have more cortisol, anyway. So you may have a harder time dealing with stressful situations.

Malaria
Type O blood may help ward off this disease. You can get malaria when an infected mosquito bites you. The parasite that causes it has a harder time attaching itself to type O blood cells.