Participant recruitment and selection of patients for inclusion (n=1851)
| Characteristic | No. |
| Consent obtained from parents of healthy children between ages 12 and 38 months enrolled in the TARGet Kids! cohort | 4995 |
| Exclusion criteria | |
| 1. No maternal ethnicity data | 481 |
| 2. No serum ferritin data | 2413 |
| 3. Serum ferritin value>200 µg/L | 1 |
| 4. CRP≥10 mg/L or missing | 61 |
| 5. Receiving iron supplementation | 44 |
| 6. Receiving multivitamins with iron | 65 |
| 7. Receiving both iron supplementation and multivitamins with iron | 1 |
| 8. Missing iron supplementation data | 78 |
| Final cohort | 1851 |
CRP, C reactive protein.