Inhibition of food iron absorption by coffee

Am J Clin Nutr. 1983 Mar;37(3):416-20. doi: 10.1093/ajcn/37.3.416.

Abstract

Dual isotope studies were performed in iron replete human subjects to evaluate the effect of coffee on nonheme iron absorption. A cup of coffee reduced iron absorption from a hamburger meal by 39% as compared to a 64% decrease with tea, which is known to be a potent inhibitor of iron absorption. When a cup of drip coffee or instant coffee was ingested with a meal composed of semipurified ingredients, absorption was reduced from 5.88% to 1.64 and 0.97%, respectively, and when the strength of the instant coffee was doubled, percentage iron absorption fell to 0.53%. No decrease in iron absorption occurred when coffee was consumed 1 h before a meal, but the same degree of inhibition as with simultaneous ingestion was seen when coffee was taken 1 h later. In tests containing no food items, iron absorption from NaFeEDTA was diminished to the same extent as that from ferric chloride when each was added to a cup of coffee. These studies demonstrate that coffee inhibits iron absorption in a concentration-dependent fashion.

Publication types

  • Clinical Trial
  • Comparative Study
  • Controlled Clinical Trial
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Anemia / etiology
  • Chlorides
  • Coffee / adverse effects*
  • Edetic Acid / pharmacology
  • Female
  • Ferric Compounds / pharmacology
  • Ferritins / blood
  • Hematocrit
  • Humans
  • Intestinal Absorption*
  • Iron / metabolism*
  • Male
  • Middle Aged
  • Time Factors

Substances

  • Chlorides
  • Coffee
  • Ferric Compounds
  • Ferritins
  • Edetic Acid
  • Iron
  • Fe(III)-EDTA
  • ferric chloride