Iron status in early childhood is modified by diet, sex and growth: Secondary analysis of a randomized controlled vitamin D trial

Abstract

Background & aims: During early childhood the risk of iron deficiency (ID) is high. Serum ferritin serves as a marker of iron status. We explored prevalence of ID and iron deficiency anemia (IDA), and identified determinants of iron status in infants and toddlers. Methods: We performed a secondary analysis of the Vitamin D intervention in infants (VIDI) study in Finnish healthy term infants. According to study protocol, at 12-and 24-months of age iron status, growth and dietary intakes were evaluated. ID was defined as serum ferritin <10 mg/L and IDA as serum ferritin <10 mg/L and Hb <112 g/L. For the present study, altogether 766 children provided data (N ¼ 498 infants at 12 months, N ¼ 508 toddlers at 24 months). Results: ID prevalence increased from 14% in infants to 20% in toddlers. IDA prevalence was 3% at both time points. In infants, ID and IDA were more common in boys than in girls (19% vs. 9%, p ¼ 0.001 and 5% vs. 1%, p ¼ 0.039) but no sex-difference in toddlers was observed. Of infants, 30% had daily iron intake below average requirement of 5 mg/day. Higher daily iron intake per body weight (mg/kg) independently associated with higher infant serum ferritin (B (95% CI) 0.30 (0.04, 0.56), p ¼ 0.026). Correlation between iron intake and ferritin was stronger in infants with ID than in infants without ID. Breastfeeding was more common (63% vs. 35%, p < 0.001) among ID infants than in infants without ID. In toddlers, frequent consumption of milk products independently associated with lower ferritin (B (95% CI) À0.03 (À0.05, À0.01), p ¼ 0.001). Consumption of meat and fish associated with better iron status. Serum ferritin at both time points associated with duration of gestation and growth. The association of growth and ferritin was age-dependent in boys, while in girls, faster growth associated consistently with lower ferritin. Conclusions: In Northern European healthy infants and toddlers ID is common. The intake of iron remains below recommendations and food consumption and iron intake associate with iron status. Further studies are warranted to assess significance of ID on child development and clinical health outcomes. The project protocol is registered at ClinicalTrials.gov: NCT01723852.

Prevalence and Factors Associated with Iron Deficiency Anaemia among Children Aged 6-23 Months in Southwestern Uganda

“…This could be explained by the fact that compared to girls, boys have a higher pre- and postnatal growth rate but with low iron storage states due to the observed larger intestinal iron loss, lower absorption, and more frequent infections [ 37 – 41 ]. The study findings agree with a study in Finland where iron deficiency and IDA were more prevalent in boys compared to girls (19% vs. 9%) [ 42 ]. It also concurs with a study in western Kenya where male children had an increased risk for ID compared to females [ 43 ] and in Pakistan, being female was associated with reduced odds for IDA [ 38 ].…”

Prevalence and factors associated with Iron deficiency anaemia among children aged 6-23 months in southwestern Uganda.

“…This could be explained by the fact that compared to girls, boys have a higher pre-and postnatal growth rate but with low iron storage states due to the observed larger intestinal iron loss, lower absorption, and more frequent infections . (Habib et al, 2016;Joo et al, 2016;Kuziga et al, 2017;Wieringa et al, 2007;Woldie et al, 2015) The study ndings agree with a study in Finland where iron de ciency and IDA were more in boys compared to girls (19% vs. 9%) (Holmlund-suila et al, 2022). It also concurs with a study in western Kenya where male children had an increased risk for ID compared to females (Foote et al, 2013) and in Pakistan, being female was associated with reduced odds for IDA (Habib et al, 2016).…”

Iron deficiency anaemia and its associated factors: A cross-sectional study among children aged 6-23 months in southwestern Uganda

“…This could be explained by the fact that compared to girls, boys have a relatively higher pre and post-natal growth rate but with low iron storage states due to observed larger intestinal iron loss, lower absorption, and more frequent infections (38)(39)(40)(41)(42). The study ndings agree with a study in Finland where iron de ciency and IDA were more in boys compared to girls (19% vs. 9%) (43). It also concurs with a study in western Kenya where male children had an increased risk for ID compared to females (44) and in Pakistan, being female was associated with reduced odds for IDA (40).…”