Aims: To describe interactions between risk factors for iron deficiency (ID).
Methods: A random community sample of 316 children 6–23 months old of whom 13% had ID. Risk factors for ID were determined using logistic regression. Relative risks (RR) and 95% confidence intervals (95%CIs) were estimated. An additive relationship between risk factors was present if the RR of ID when both factors were present exceeded the sum of individual RRs of ID.
Results: Independent risk factors for ID in a multivariate model were prematurity/low birthweight (RR 4.82, 95%CI 1.57–7.42), increased body mass index (5.57, 1.41–12.18), eating fruit only as a snack (3.48, 1.38–7.28), having no milk formula (4.40, 2.06–7.27), daily cow's milk (4.71, 1.99–8.56) and having only homemade first solids (2.91, 1.01–6.40). Eating fruit only as a snack had an additive relationship with three other dietary risk factors: no milk formula (RR 11.75, 95%CI 4.58–19.46), cow's milk daily (13.48, 1.20–42.37) and only homemade first solids (8.66, 3.43–14.76). Larger body mass had an additive relationship with four dietary factors: no milk formula (RR 14.69, 95%CI 1.95–24.00), fruit only as a snack (10.11, 4.59–16.36), cow's milk daily (12.28, 5.97–21.95) and only homemade first solids (7.05, 1.27–16.27). Prematurity/low birthweight had an additive relationship with two dietary risk factors: no milk formula (RR 9.16, 95%CI 2.42–12.11) and only homemade first solids (7.15, 1.47–9.73).
Conclusions: Risk factors for ID interact to place young children at high risk of ID.