Blood donation? Great. Take some iron after.

Thank you if you are considering a blood donation. According to a clinical trial recently published in JAMA, iron supplementation after blood donation may prevent you from becoming anemic and very likely greatly reduce the time it takes to recover a normal ferritin level. The authors state:

"Although blood donation is allowed every 8 weeks in the United States, recovery of hemoglobin to the currently accepted standard (12.5 g/dL) is frequently delayed, and some donors become anemic."

They structured their study of iron supplementation with blood donation to...

 "...determine the effect of oral iron supplementation on hemoglobin recovery time (days to recovery of 80% of hemoglobin removed) and recovery of iron stores in iron-depleted ("low ferritin," ≤26 ng/mL) and iron-replete ("higher ferritin," >26 ng/mL) blood donors."

In a randomized, nonblinded clinical trial they gave one tablet of ferrous gluconate (37.5 mg of elemental iron) daily, or none, for 24 weeks after a blood donation of one unit (500 mL), then measured the time to recovery of 80% of the decrease in their subjects' hemoglobin and the time to recovery of their ferritin level to starting level.

Taking supplemental iron made a big difference in recovery from blood donation

"The mean baseline hemoglobin levels were comparable in the iron and no-iron groups and declined from a mean (SD) of 13.4 (1.1) g/dL to 12.0 (1.2) g/dL after donation in the low-ferritin group and from 14.2 (1.1) g/dL to 12.9 (1.2) g/dL in the higher-ferritin group. Compared with participants who did not receive iron supplementation, those who received iron supplementation had shortened time to 80% hemoglobin recovery in both the low-ferritin (mean, 32 days) and higher-ferritin groups (31 days). Median time to recovery to baseline ferritin levels in the low-ferritin group taking iron was 21 days. For participants not taking iron, recovery to baseline was longer than 168 days. Median time to recovery to baseline in the higher-ferritin group taking iron was 107 days, and for participants not taking iron, recovery to baseline was longer than 168 days. Recovery of iron stores in all participants who received supplements took a median of 76 days; for participants not taking iron, median recovery time was longer than 168 days. Without iron supplements, 67% of participants did not recover iron stores by 168 days."

Clinical Note

Ferritin levels above 26 ng/mL but below 50 ng/ml are still not good enough. See the earlier posts Fatigue commonly caused by iron deficiency without anemia, Borderline anemia increases risk of death in coronary disease, and Even mild anemia has a big impact (and type 'anemia' in the search box for others) for validation of functional reference ranges.The authors' conclusion logically applies to everyone donating blood:

"Among blood donors with normal hemoglobin levels, low-dose iron supplementation, compared with no supplementation, reduced time to 80% recovery of the postdonation decrease in hemoglobin concentration in donors with low ferritin (≤26 ng/mL) or higher ferritin (>26 ng/mL)."