The effect of iron on vitamin D level in children with combined iron and vitamin D deficiency

Introduction: Iron deficiency (ID) and vitamin D deficiency (VDD) are two common nutritional problems. Recently, an association between these two disorders has been suggested that remains to be definitely confirmed.Objectives: Our aim was to compare treatment with iron, vitamin D, and their combination on serum levels of vitamin D in children with ID and vitamin D insufficiency (VDI). Patients and Methods: A total of 90 patients with low levels of ferritin and vitamin D were assigned to three groups of 30 each: treatment with iron for ID, treatment with vitamin D, and co-treatment with vitamin D and iron. Levels of vitamin D and ferritin were measured before and 3 months after treatment. Data analysis was entirely conducted by paired t-test, one-way ANOVA using SPSS 19. Results: Serum vitamin D levels significantly changed 3 months after treatment in the vitamin D and iron+ vitamin D groups (P < 0.01), but not in the iron group (P = 0.68). Comparison of mean changes in serum vitamin D levels was not significantly different between the iron+ vitamin D and vitamin D groups (P = 0.774). Conclusion: Iron supplementation alone could not significantly increase vitamin D levels in studied children. Vitamin D supplementation and vitamin D+ iron supplementation caused similar effects on serum vitamin D levels, and management of ID did not have any incremental effect on vitamin D levels in children. It is necessary to use vitamin D supplementation to control and treat VDD.