The authors present a well-conducted randomized study of the effect of iron administration to non-anemic menstruating women. Non-anemic women complaining of fatigue were randomized to receive oral iron or placebo. Iron administration resulted in a greater decrease in fatigue compared to placebo. This result could not be attributed to other factors such as depression or anxiety, which remained unaffected by iron administration.
One of the results of iron deficiency is the decreased activity of iron-dependent enzymes critical for muscle function. Muscle dysfunction could result in the feeling of fatigue. This was shown by Finch et al. in a rat experiment: the running ability of iron deficient rats was impaired due to a decrease in a mitichondrial enzyme, a metalloprotein containing non-heme iron (Finch CA et al. J Clin Invest 1976;58:447-453).
This article is a worthwhile read!
– Alice Maniatis