Alterations in calcium, magnesium, iron, and zinc metabolism by dietary cholestyramine

Dig Dis Sci. 1985 May;30(5):477-82. doi: 10.1007/BF01318182.


Cholestyramine is an effective drug for the reduction of plasma cholesterol because of its ability to sequester intestinal bile acids. Since metabolic alterations, including diminished intestinal absorption of vitamin D and osteomalacia have been reported with long-term use of this resin, the influence of cholestyramine on dietary balance of four mineral elements has been investigated. Wistar-strain rats were fed either a 2% cholestyramine or control diet for one month. Dietary intakes and fecal and urinary excretions of calcium, magnesium, iron, and zinc were determined using atomic absorption spectrophotometry during three, 3-day balance periods. Cholestyramine-fed rats had a net negative balance for calcium and a lower net positive balance for magnesium, iron, and zinc than the controls. Other effects of cholestyramine were an increased urinary excretion of calcium and magnesium, a decreased urinary zinc, and an alkalinization of urine. Blood and tissue cation content was unchanged except for a reduction in serum magnesium with resin feeding. Alterations in calcium, magnesium, and zinc metabolism might be explained by inadequate vitamin D absorption from the intestine followed by an increased secretion of parathyroid hormone. A diminished iron absorption due to resin binding could account for the reported disturbance in iron balance.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Calcium / metabolism*
  • Calcium / urine
  • Calcium, Dietary / metabolism
  • Cholestyramine Resin / pharmacology*
  • Feces / analysis
  • Hydrogen-Ion Concentration
  • Intestinal Mucosa / drug effects
  • Intestinal Mucosa / metabolism
  • Iron / metabolism*
  • Iron / urine
  • Magnesium / blood
  • Magnesium / metabolism*
  • Magnesium / urine
  • Male
  • Rats
  • Rats, Inbred Strains
  • Spectrophotometry, Atomic
  • Zinc / metabolism*
  • Zinc / urine


  • Calcium, Dietary
  • Cholestyramine Resin
  • Iron
  • Magnesium
  • Zinc
  • Calcium