I'm wondering how much giving blood will drop your Hematocrit? Also if anyone knows, I would be interested in finding out how much it drops Feritin?[/QUyourOTE]
If your ferritin/iron levels are not in a healthy range or you are not getting enough iron through diet/supplementation and you choose to donate frequently as in every 56 days be prepared to run into low ferritin/iron issues as you will loose roughly 225-250 mg iron/ 1 pint (500 ml) whole blood.
For males donating more than 3-4 times per year can make one more prone to having low ferritin/iron stores in the long run so daily intake of iron through diet especially heme iron ( liver/red meat/oysters) or supplementation with iron is a must and is critical to avoid low ferritin/iron issues from too frequent donations.
It is basically a catch 22 as in order for many to keep hematocrit/hemoglobin levels in a healthy range through donating blood, frequent donations are usually needed and many men/women do not understand that if ones ferritin/iron levels are already sub-par than frequent donations will make levels worse.
The main issue is once ferritin/iron get too low one can experience a host of negative effects as healthy levels are critical to overall health and most importantly when levels are very low it can take 3-4 months to get levels back up and in order to achieve this high dosages of iron supplementation are needed along the lines of what Vince Carter takes as basic iron supplementation in low doses as in 10-30 mg/day will not work.
If you run into low ferritin/iron issues than you are going to have to stop donating blood for 3-4 months to get your levels back up before donating again and by that time your hematocrit/hemoglobin has creeped back up to unhealthy levels.
Worse case scenario is once ferritin/iron is too low in some cases high dose supplementation will not work for some and than you may be looking at injection/intravenous iron.
It is a fine line to walk when donating frequently to keep hematocrit/hemoglobin in a healthy range along with good levels of ferritin/iron.