title: Calcium intake is weakly but consistently negatively associated with iron status in girls and women in six European countries.
abstract: Several studies indicate that intake of calcium can inhibit iron absorption especially when taken simultaneously. In the CALEUR study, a cross-sectional study among girls (mean 13.5 y) and young women (mean 22.0 y) in six European countries, the association between calcium intake and iron status was studied. In 1,080 girls and 524 women, detailed information on calcium intake was collected by means of a 3-d food record, and serum ferritin, serum iron, serum transferrin and transferrin saturation were measured as indicators of iron status. The mean levels of serum iron, ferritin and transferrin were 15.8 +/- 6.1 mmol/L, 34.5 +/- 19.1 microg/L and 3. 47 +/- 0.47 g/L, respectively, in girls and 16.9 +/- 7.5 mmol/L, 40. 2 +/- 30.5 and microg/L, 3.59 +/- 0.60 g/L, respectively, in women. A consistent inverse association between calcium intake and serum ferritin was found, after adjusting the linear regression model for iron intake, age, menarche, protein, tea and vitamin C intake and country, irrespective of whether calcium was ingested simultaneously with iron. The adjusted overall regression coefficients for girls and women were -0.57 +/- 0.20 and -1.36 +/- 0.46 per 100 mg/d increase in calcium intake, respectively. Only in girls, transferrin saturation as a measure for short-term iron status was inversely associated with calcium intake (adjusted overall coefficient -0.18 +/- 0.08). However, analysis per country separately showed no consistency. We conclude that dietary calcium intake is weakly inversely associated with blood iron status, irrespective of whether calcium was ingested simultaneously with iron.
authors.affiliation: Division of Human and Animal Nutrition, TNO Nutrition and Food Research Institute, 3700 AJ Zeist, The Netherlands.
authors.forename: L P
authors.initials: LP
authors.lastname: van de Vijver
authors.forename: A F
authors.initials: AF
authors.lastname: Kardinaal
authors.forename: J
authors.initials: J
authors.lastname: Charzewska
authors.forename: M
authors.initials: M
authors.lastname: Rotily
authors.forename: P
authors.initials: P
authors.lastname: Charles
authors.forename: M
authors.initials: M
authors.lastname: Maggiolini
authors.forename: S
authors.initials: S
authors.lastname: Ando
authors.forename: K
authors.initials: K
authors.lastname: Väänänen
authors.forename: B
authors.initials: B
authors.lastname: Wajszczyk
authors.forename: J
authors.initials: J
authors.lastname: Heikkinen
authors.forename: A
authors.initials: A
authors.lastname: Deloraine
authors.forename: G
authors.initials: G
authors.lastname: Schaafsma
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging; D001205:Ascorbic Acid / Q000008:administration & dosage; D001827:Body Height; D001835:Body Weight; D002136:Calcium, Dietary / Q000008:administration & dosage*; D002648:Child; D004044:Dietary Proteins / Q000008:administration & dosage; D004347:Drug Interactions; D002149:Energy Intake; D005060:Europe; D005260:Female; D005293:Ferritins / Q000097:blood; D006801:Humans; D007501:Iron / Q000097:blood*; D019266:Iron, Dietary / Q000008:administration & dosage; D009752:Nutritional Status; D014168:Transferrin / Q000378:metabolism
chemical_list: D002136:Calcium, Dietary; D004044:Dietary Proteins; D019266:Iron, Dietary; D014168:Transferrin; D005293:Ferritins; D007501:Iron; D001205:Ascorbic Acid