Sypes EE, et al. - In this cross-sectional study of healthy children 1-3 years of age, researchers investigated the relationship between body mass index (BMI) and iron deficiency in early childhood, taking into account the influence of low-grade systemic inflammation. Children with CRP ≥10 mg/L have been excluded, as this may indicate acute systemic inflammation. In children 1-3 years of age, higher BMI z score (zBMI) was linked to lower serum ferritin levels. Of the 1607 children, 20% were classified as zBMI >1, 13% had iron deficiency and 18% had low-grade inflammation. There was a 1.51 µg/L decline in median serum ferritin level and a 28% increased odds of iron deficiency for each additional 1.0 unit of zBMI. In young children, higher BMI might be a risk factor for iron deficiency.