Calcified Tissue International

, Volume 46, Issue 5, pp 300–304 | Cite as

Absorbability of calcium sources: The limited role of solubility

  • Robert P. Heaney
  • Robert R. Recker
  • Connie M. Weaver
Clinical Investigations

Summary

Fractional absorption of seven chemically defined calcium sources was measured in normal adult women under standardized load conditions. Solubility of the sources in water at neutral pH ranged from a low of 0.04 mM to a high of 1500 mM. The relationship of solubility to absorbability was weak. In the range from 0.1 to 10 mM, within which most calcium supplement sources fall, there was no detectable effect of solubility on absorption. Data from four food sources are presented for comparison. Absorbability of food calcium was not clearly related to absorbability of the dominant chemical form in the food concerned. These findings suggest that (1) even under controlled, chemically defined conditions, solubility of a source has very little influence on its absorbability; and (2) absorbability of calcium from food sources is determined mainly by other food components.

Key words

Calcium absorption Solubility absorbability relationships Calcium salts Food calcium sources Biovailability 

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References

  1. 1.
    Pak CYC, Avioli LV (1988) Factors affecting absorbability of calcium from calcium salts and food. Calcif Tissue Int 43:55–60PubMedCrossRefGoogle Scholar
  2. 2.
    United States Pharmacopeial Convention (1987) United States Pharmacopeia, 21st revision: National Formulary, 16th ed (suppl 5) Rockville, MD: The Convention, pp 2353–2354Google Scholar
  3. 3.
    Pak CYC, Poindexter J, Finlayson B (1989) A model system for assessing physicochemical factors affecting calcium absorbability from the intestinal tract. J Bone Mineral Res 4:119–127Google Scholar
  4. 4.
    Haynes RJ Jr, Murad F (1985) Agents affecting calcification: calcium, parathyroid hormone, calcitonin, vitamin D, and other compounds. In: Gilman AG, Goodman LS, Rall TW, Murad F (eds) The pharmacological basis of therapeutics, 7th ed. McMillan Publishing Co, New York, Chapter 65, pp 1517–1522Google Scholar
  5. 5.
    Recker RR (1985) Calcium absorption and achlorhydria. N Engl J Med 313:70–73PubMedCrossRefGoogle Scholar
  6. 6.
    Bo-Linn GW, Davis GR, Buddrus DJ, Morawski SG, Santa Ana C, Fordtran JS (1984) An evaluation of the importance of gastric acid secretion in the absorption of dietary calcium. J Clin Invest 73:640–647PubMedCrossRefGoogle Scholar
  7. 7.
    Heaney RP, Weaver CM (1989) Oxalate: effect on calcium absorption. Am J Clin Nutr 50:830–832PubMedGoogle Scholar
  8. 8.
    Heaney, RP, Weaver CM, Recker RR (1988) Calcium absorbability from spinach. Am J Clin Nutr 47:707–709PubMedGoogle Scholar
  9. 9.
    Heaney RP, Weaver CM (in press) Calcium absorption from kale. Am J Clin NutrGoogle Scholar
  10. 10.
    Heaney RP, Smith KT, Recker RR, Hinders SM (1989) Meal effects on calcium absorption. Am J Clin Nutr 49:372–376PubMedGoogle Scholar
  11. 11.
    Recker RR, Bammi A, Barger-Lux J, Heaney RP (1988) Calcium absorbability from milk products, an imitation milk, and calcium carbonate. Am J Clin Nutr 47:93–95PubMedGoogle Scholar
  12. 12.
    Bronner F (1962) Experimental studies of calcium absorption in man. Bibl Nutr Dieta 3:22–31Google Scholar
  13. 13.
    DeGrazia JA, Ivanovich P, Fellows P, Rich C (1965) A double isotope method for measurement of intestinal absorption of calcium in man. J Lab Clin Med 66:822–829PubMedGoogle Scholar
  14. 14.
    Heaney RP, Recker RR (1985) Estimation of true calcium absorption. Ann Int Med 103:516–521PubMedGoogle Scholar
  15. 15.
    Heaney RP, Recker RR (1988) Estimating true fractional calcium absorption (Letter) Ann Int Med 108:905–906PubMedGoogle Scholar
  16. 16.
    Heaney RP, Recker RR, Stegman MR, Moy AJ (1989) Calcium absorption in women: relationships to calcium intake, estrogen status, and age. J Bone Miner Res 4:469–475PubMedCrossRefGoogle Scholar
  17. 17.
    Encyclopedia of Chemical Toxicology, 3rd ed, vol. 17 (1982) John Wiley & Sons, New YorkGoogle Scholar
  18. 18.
    Smith KT, Heaney RP, Flora L, Hinders SM (1987) Calcium absorption from a new calcium delivery system. Calcif Tissue Int 41:351–352PubMedCrossRefGoogle Scholar
  19. 19.
    Handbook of Chemistry and Physics (1988) 69th ed. CRC Press, Inc, Boca RatonGoogle Scholar
  20. 20.
    Heaney RP, Recker RR, Hinders SM (1988) Variability of calcium absorption. Am J Clin Nutr 47:262–264PubMedGoogle Scholar
  21. 21.
    Sheikh MS, Santa Ana CA, Nicar MJ, Schiller LR, Fordtran JS (1987) Gastrointestinal absorption of calcium from milk and calcium salts. N Engl J Med 317:532–536PubMedCrossRefGoogle Scholar
  22. 22.
    Ashmead HD, Graff DJ, Ashmead HH (1985) Intestinal absorption of metal ions and chelates. Charles C Thomas, Springfield, IllinoisGoogle Scholar
  23. 23.
    Carr CJ, Shangraw RF (1987) Nutritional and pharmaceutical aspects of calcium supplementation. Am Pharm NS 27:49–57Google Scholar

Copyright information

© Springer-Verlag New York Inc 1990

Authors and Affiliations

  • Robert P. Heaney
    • 2
  • Robert R. Recker
    • 2
  • Connie M. Weaver
    • 1
  1. 1.Department of Foods and NutritionPurdue UniversityWest LafayetteUSA
  2. 2.Center for Hard Tissue ResearchCreighton UniversityOmahaUSA

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