This study, published on-line in CMAJ.ca, July 9, 2012, looked at the effects of iron supplementation in women with low ferritin levels but normal hemoglobin and hematocrit levels. In the past, if you had low ferritin but normal hemoglobin you were not considered anemic and the low ferritin was not considered a cause of fatigue. This study found that this is not the case and that supplementation with iron reduced fatigue in low ferritin/ normal hemoglobin women. http://www.cmaj.ca/content/early/2012/07/09/cmaj.110950.full.pdf They conclude: " Iron supplementation should be considered for women with unexplained fatigue who have ferritin levels below 50 micrograms per milliliter". This is very interesting to me since I have had very low ferritin ( ranging from 11 to 25 : normal ferritin is 80-300 ) for the last ten years but always have had normal hemoglobin, hematocrit and RBC's. All the doctors I have seen, including an ME/CFS specialist, weren't concerned about the low iron since they were taught to look at hemoglobin results. It is only a few naturopaths who believed low ferritin was causing a problem. I don't think it is the cause of my illness but if getting my ferritin levels up will reduce some of my fatigue then that is a good thing. Every little bit of improvement helps.