Oral ferrous sulphate supplementation has greater efficacy, but lower tolerance than iron (III)-hydroxide polymaltose complexes in exercising women with low iron stores

BACKGROUND & AIMS: Iron deficiency (ID) is a global health condition that predominately affects women. Although oral iron supplementation is an effective treatment strategy for this issue, gastrointestinal complaints are common, and if persistent, may lead to poor compliance. The efficacy of different iron formulations which claim to improve tolerance is unclear. This study assessed the efficacy and tolerability of ferrous sulphate (FS) and iron (III)-hydroxide polymaltose complex (IPC) supplementation in three different cohorts of women.. METHODS: This study implemented a 12-week, single-blind, randomized controlled trial. Eligible participants had a serum ferritin concentration of 0.05). The IPC group had a lower symptom rate compared to FS (28 % vs. 33 %; p < 0.001).. CONCLUSIONS: FS was superior in repleting ferritin concentrations after 12 weeks compared with IPC; however, FS also resulted in a greater number and severity of GI symptoms than IPC. Our data shows FS is the superior iron formulation for ID treatment, however future research should continue to address how to improve FS tolerance.. This trial was registered at https://www.anzctr.org.au/Trial/Registration/TrialReview as ACTRN12623000529640.