In this case-control study the association between the approaches used to feed infants, together with known family and environmental factors, and the occurrence of atopic illness in toddlers between the ages of 4 months to 3 years in Hong Kong was examined. A total of 206 subjects were recruited from April to June of 2014. The results obtained by binary logistic regression indicated that atopy is associated with boys (OR 2.072, CI 1.089-3.941), the maternal use of antibiotics in utero or while breast feeding (OR 2.276, CI 1.151-4.504), the later commencement of mixed feeding (OR 2.497, CI 1.025-6.082), breast feeding exclusively for 3 months (OR 1.972, CI 1.009-3.857), and having a mother who was diagnosed with eczema (OR 4.510, CI 1.764-11.530). Although an exclusive reliance on breast feeding has been shown to be predictive of atopy among toddlers, the positive qualities of breast milk cannot be ignored. A further study of the contents and nutritional values of breast milk is warranted.