Restorative effect of bean ferritin iron on low hemoglobin level in premenopausal women with menstruation-induced anemia: A randomized, double-blind placebo-controlled intergroup trial

Background: Recently, bean ferritin has been attracting considerable attention as a new source of iron, that is available to vegetarians. Although high rates of iron absorption and bioavailability from this protein have been reported, clinical data on its efficacy remain scarce. Objective: In this study, we administered bean ferritin iron to premenopausal Japanese women for nine weeks, starting immediately after menstruation, to evaluate their recovery from low hemoglobin levels as one sign of anemia. Methods: Participants in the test supplement group received an iron intake of 5 mg from one capsule containing bean extract (SloIron®) for five weeks, which was increased to 10 mg (i.e., two capsules) from the 6th to the 9th week. The study evaluated the change in hemoglobin levels as the primary endpoint, and hematocrit, red blood cell count, serum iron, MCH (mean corpuscular hemoglobin), MCHC (mean corpuscular hemoglobin concentration), serum ferritin, TSAT (TIBC), serum zinc, serum copper, anemia symptoms questionnaire, OSA sleep inventory, and the anti-fatigue questionnaire as the secondary endpoints. Results: Our results showed a significant difference (P=0.03) in the change in hemoglobin levels between the groups after nine weeks of intake, confirming the restorative effect of bean ferritin on low hemoglobin levels caused by menstruation. Moreover, a significant difference (P=0.01) was observed in the amount of change in MCHC between the two groups after five weeks of intake, and after nine weeks of intake, a significant difference in the change in both MCH (P=0.02) and MCHC (P<0.01) was observed between the groups. A significant difference (P=0.03) was observed in the change in serum ferritin levels after nine weeks of intake. Conclusion: The study confirmed that iron supplementation from bean ferritin is an effective treatment for low hemoglobin and low ferritin levels caused by menstruation. Keywords: Ferritin, Bean ferritin, Menstruation, Serum iron, Hemoglobin