Microbiome of Donor Iron Deficient Study

The colonic microbiome, the community of bacteria living in our gut, is essential in human
health and disease. Iron is an essential nutrient for both bacteria and humans. In the United
States, of the donors who provided the ~15 million units of red blood cells that were
collected for transfusion, 69% were repeat donors. Although iron deficiency is surprisingly
prevalent in first-time donors, its prevalence is even higher in these particularly
altruistic frequent donors, (i.e., up to 49% and 66% of male and female repeat donors,
respectively), manifested as iron depletion or iron-deficient erythropoiesis. Iron deficiency
from blood donation is associated with fatigue, restless leg syndrome, decreased physical
endurance and work capacity, and impaired concentration, attention, and other neurocognitive
functions; however, these conclusions are not based on definitive studies and have not yet
changed blood donation policy. The goal is to conduct a prospective, double-blind, randomized
controlled trial, recruiting 60 healthy regular donors who meet donation standards, while
exhibiting iron-deficient erythropoiesis by laboratory test criteria. In this ancillary
study, we will determine what effect donor iron deficiency and IV iron repletion have on the
gut microbiome.

Inclusion Criteria:

- Current participant of the associated randomized controlled trial conducted at
Columbia University Medical Center (therefore invited to participate in this optional
ancillary study).

Exclusion Criteria:

- Not a current participant of the associated randomized controlled trial conducted at
Columbia University Medical Center.