Knowledge of type of the blood can help you determine how much you are vulnerable to heart disease or stroke, a new research says.

Researchers at Harvard Medical School and Harvard School of Public Health have discovered that that blood type “O” offers more protection against heart attack and stroke, while people with less common blood type “AB” appears to be more at risk.

People with blood types “A” and “B” are also at a slightly higher risk of heart disease and stroke compared to those with the most common type O.

Compared to people with blood type “O,” the findings say, people with blood type “AB” are 23 per cent more likely to suffer heart disease, while people with blood type “A” and “B” are at 5 per cent and 11 per cent increased risk, respectively.

Previous researchers also suggest that Blood types “A” is tied to higher levels of bad cholesterol called LDL, while the blood type “AB” is linked to inflammation, which also lead to heart disease.

Researcher Lu Qi, MD, PhD, said, “People can’t change their blood type. But we may be able to use this information to help determine a patient’s risk for heart disease and how aggressively to treat them.”

In the U. S., type “O” is the most common type of blood, with around 45 per cent of whites, 57 per cent of Hispanics, and 51 per cent of African-Americans, having this blood type. The “AB” blood type is much rarer, with just 4 per cent of whites and African-Americans, and 2 per cent of Hispanics having it.