Iron Absorption in Young Indian Women: The Interaction of Iron Status With the Influence of Tea and Ascorbic Acid

Am J Clin Nutr. 2008 Apr;87(4):881-6. doi: 10.1093/ajcn/87.4.881.

Abstract

Background: Ascorbic acid (AA) enhances and tea inhibits iron absorption. It is unclear whether iron status influences the magnitude of this effect.

Objective: We evaluated the influence of the iron status of young women on iron absorption from a rice meal with or without added tea or AA.

Design: Two stable-isotope iron absorption studies were made in 2 groups of 10 subjects with iron deficiency anemia (IDA) and 10 subjects who were iron replete (control subjects). In study 1, the reference rice meal was fed alone or with 1 or 2 cups of black tea. In study 2, the reference meal was fed alone or with AA (molar ratio to iron, 2:1 or 4:1). Iron absorption was measured by the erythrocyte incorporation of (57)Fe and (58)Fe labels at 14 d.

Results: Mean fractional iron absorption from the reference rice meal was approximately 2.5 times as great in the IDA group as in the control group (P < 0.05). The consumption of 1 or 2 cups of tea decreased iron absorption in the control subjects by 49% (P < 0.05) or 66% (P < 0.01), respectively, and in the IDA group by 59% or 67% (P < 0.001 for both), respectively. AA (molar ratio to iron, 2:1 or 4:1) increased iron absorption by 270% or 343%, respectively, in control subjects and by 291% or 350%, respectively, in subjects with IDA (P < 0.001).

Conclusions: The inhibitory effect of tea and the enhancing effect of AA on iron absorption were similar in the 2 groups. Overall differences in iron absorption in the 2 groups, however, continued to be dictated by iron status.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Anemia, Iron-Deficiency / blood
  • Anemia, Iron-Deficiency / diet therapy
  • Anemia, Iron-Deficiency / metabolism*
  • Ascorbic Acid / pharmacology*
  • Biological Availability
  • Case-Control Studies
  • Cross-Over Studies
  • Erythrocytes / chemistry
  • Female
  • Humans
  • Intestinal Absorption / drug effects
  • Iron Isotopes
  • Iron, Dietary / pharmacokinetics*
  • Nutritional Status*
  • Tea / chemistry*

Substances

  • Iron Isotopes
  • Iron, Dietary
  • Tea
  • Ascorbic Acid