A growing pile of clinical evidence shows that low iron stores and mild anemia may be beneficial in some cases, by offering protection from infections such as malaria and tuberculosis, and by helping combat chronic diseases.
The study said that treating kids with anemia with iron supplementation may remove this protective effect of iron deficiency.
The University of North Carolina at Chapel Hill researchers, along with colleagues from the Medical Research Council Unit in The Gambia, Africa, and the London School of Hygiene & Tropical Medicine, have proven that these concerns valid after finding iron deficiency anemia actually protects children against the blood-stage of Plasmodium falciparum malaria and treating anemia with iron supplementation removes this protective effect.
They studied the red-blood cells of 135 anemic children aged 6-24 months in a malaria-endemic region of The Gambia where sickle-cell trait was also common. The children received iron through micronutrient powder for 84 days as part of an iron supplementation trial. Red blood cells from the children were analyzed at baseline, day 49 and day 84.
Previous studies had shown a protective effect from malaria in children having the sickle-cell trait. However, the researchers found that on a population-wide basis anemia reduced the blood-stage of malaria by 16% while the sickle-cell trait only reduced it by 4%.
“Our finding that anemia offers greater natural protection against blood-stage malaria infection than sickle-cell trait has led us to formulate the interesting hypothesis that the widespread prevalence of anemia in people of African descent is a genetic signature of malaria,” said Morgan Goheen, Ph.D., the study’s lead author and a graduate student in the UNC Department of Microbiology and Immunology.
The study was published in journal of EBioMedicine.
Deficits in invasion and growth for blood stage P. falciparum were reserved when anemic children had received seven weeks of Iron supplementation. Prior work by the same research team suggests that the increased invasion and growth rates following iron supplementation are caused by the parasites’ strong preference for young red blood cells.
M.D. Ph.D., lead scientist on the project at the MRC Unit in The Gambia, Carla Cerami said, “This study is elegant in its simplicity, yet remains one of the most substantial and systematic attempts to unveil the cellular-level relationship between anemia, iron supplementation and malaria risk.”
These new field results consolidate the evidence that iron supplementation increases the risk of P. falciparum malaria and provide support for the use of malaria prophylaxis by iron supplementation programs, especially during the critical, early phases of the erythroid recovery.