title: Iron stores and iron absorption: effects of repeated blood donations.
abstract: We assessed changes in iron stores and iron absorption after repeat blood donations using a combination of biochemical measures of iron status: ferritin, hemoglobin, and transferrin saturation. Thirty-six volunteers with a mean (+/- SD) age of 67.7 +/- 3.7 y donated an average of 15 units of blood over 3.5 y. Initial iron stores were 12.45 +/- 3.09 mg/kg for men and 12.53 +/- 3.24 mg/kg for women. Of the 20 men and 16 women who completed the study, 6 men and 10 women were taking a self-selected supplement providing approximately 20 mg Fe/d. Dietary iron intake was determined to be approximately 20 mg/d for men and approximately 18 mg/d for women. Decreases in iron stores in supplemented men were not significantly different from those in nonsupplemented men: 9.52 +/- 2.57 and 11.31 +/- 2.74 mg/kg, respectively. Nonsupplemented women showed a significantly (P < 0.05) greater decline in iron stores than did supplemented women: 13.09 +/- 2.46 and 10.60 +/- 4.15 mg/kg, respectively. Mean maximal iron absorption was approximately 4.10 mg/d for men and approximately 3.55 mg/d for women regardless of iron intake.
authors.affiliation: Department of Pathology, University of New Mexico School of Medicine, Albuquerque 87131, USA.
authors.forename: P J
authors.initials: PJ
authors.lastname: Garry
authors.forename: K M
authors.initials: KM
authors.lastname: Koehler
authors.forename: T L
authors.initials: TL
authors.lastname: Simon
mesh_terms: D000042:Absorption; D000368:Aged; D001782:Blood Donors; D004032:Diet; D005260:Female; D005293:Ferritins / Q000097:blood; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007501:Iron / Q000008:administration & dosage / Q000378:metabolism* / Q000493:pharmacokinetics*; D008297:Male; D009994:Osmolar Concentration; D012016:Reference Values; D012727:Sex Characteristics; D014168:Transferrin / Q000032:analysis
chemical_list: D006454:Hemoglobins; D014168:Transferrin; D005293:Ferritins; D007501:Iron