Correction of the equation to calculate iron absorption by individual iron stores

Gwangju-jeonnam Red Cross Blood Center
127-4 song-ha dong
Nam gu
Gwangju
South Korea
E-mail: nicholas_10{at}hanmail.net

Dear Sir:

I read with great interest the article by Hallberg et al (1) in which they show an algorithm to calculate iron absorption by types of diets and individual iron stores. I am investigating the correct timing for blood donation, and Hallberg's article is very useful for predicting iron stores in a blood donor. But, when I use the equation to calculate individualized iron absorption (Equation 11 in the article), there seems to be an error.

In the equation, iron absorption by algorithm is the same as real absorption when serum ferritin (SF) is 19.06; however, Hallberg mentioned that a reference dose of 40% corresponded to an SF concentration of 23 µg/L in Appendix A of this article. Therefore, I seem to have found an error in Equation 11.

First, brackets that appeared in Equation A2 were added in error. The equation should be as follows:

Second, A6 should be

should be

ACKNOWLEDGMENTS

The authors had no conflicts of interest.

REFERENCE

1. Hallberg L, Hulthen L. Prediction of dietary iron absorption: an algorithm for calculating absorption and bioavailability of dietary iron. Am J Clin Nutr2000; 71 :1147 –60.