More than 4.5 million patients need blood transfusions each year in the U.S. and Canada.
Someone needs blood every two seconds.
Only 37 percent of the U.S. population is eligible to donate blood.
One pint of blood can save up to three lives.
There are four main red blood cell types: A, B, AB and O. Each blood type can be positive or negative for the Rh factor. AB + is the universal recipient (can receive any blood type); O – is the universal donor of red blood cells.
The amount of blood you could donate if you begin at age 17 and donate every 56 days until you reach 79 years old: 46.5 gallons.
The amount of blood in the body of an average adult: 10 pints.
You burn 650 calories per donation of one pint of blood!
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