Submitted to: Journal of Federation of American Societies for Experimental Biology
Publication Type: Abstract only
Publication Acceptance Date: 12/2/2002
Publication Date: 3/14/2003
Citation: Hunt, J.R., Johnson, L.K. 2003. Adaptation in dietary zinc absorption from whole diets: implications for determining zinc requirements [abstract]. Journal of Federation of American Societies for Experimental Biology. p. A694. Interpretive Summary:
Technical Abstract: Measurements of adaptation in Zn absorption in response to different dietary Zn intakes could improve our understanding of dietary Zn requirements. To investigate this, Zn absorption from controlled whole diets containing different amounts of Zn (Table) and with moderate amounts of animal flesh, low phytic acid and no Zn fortification, was measured by using Zn-65 radiotracer and whole body counting. Healthy men and women fed 3.4, but not those fed 5.4 to 12.9 mg Zn/2500 kcal adapted by increasing fractional Zn absorption (p<0.001; n=7-8/grp) after 4 wk of consuming the diet. Neither the amounts of Zn absorbed nor plasma Zn were affected by diet. Immediate dose/response controls appear to result in similar absolute absorption of Zn from refined, mixed diets containing a moderate range of Zn from food. Within 4 wk, adaptation to meet the homeostatic requirements of healthy US men and women did not appear necessary if low-phytate diets contained at least 5.4 to 7.7 mg/2500 kcal.