how long does it take your body to reproduce blood
Answers. Best Answer: Your plasma (the watery part of the blood that makes up most of its volume) should be replaced within a week. Normally the body can replace a pint of donated plasma in 24 hours, so I'm extrapolating from there since you lost three pints. It can take your body at least 8 weeks to replace all the red blood cells (erythrocytes) that you lost. These erythrocytes are what carry the iron in your blood. They also carry the oxygen. Less oxygen and less iron in your blood can make you look pale.