Impact of milk consumption patterns on cow's milk sensitization and allergy in at-risk children

Background: Cow's milk allergy is the most common food allergy in infants. While early peanut consumption can reduce peanut allergy risk, the effects of cow's milk formula consumption patterns on milk sensitization and allergy are not well understood. Objective: To examine the association between early cow's milk formula consumption patterns and cow's milk sensitization and allergy in high-risk infants. Methods: We conducted a secondary cross-sectional analysis of 416 infants (3-15 months) from the CoFAR study, categorized by milk consumption patterns: hospital consistent, hospital inconsistent, home only, and non-consumers. Group differences were assessed using Kruskal-Wallis and post-hoc tests. Univariate and multivariate logistic regression models estimated associations with cow's milk sensitization and allergy. Results: Hospital consistent infants had smaller SPT wheal sizes and less sensitization than hospital inconsistent and non-consumers. Early inconsistent consumption was associated with higher odds of sensitization (OR = 2.45; 95% CI: 1.24-5.05), while non-consumption was associated with lower allergy odds (OR = 0.39; 95% CI: 0.21-0.69). As clinical CMA diagnosis requires prior ingestion with reaction, lower allergy rates among non-consumers may reflect limited exposure opportunities rather than a protective effect. Home-only consumption did not significantly affect risk. Conclusions: Early cow's milk formula consumption patterns were associated with differences in cow's milk sensitization and allergy outcomes in high-risk infants. Consistent exposure was associated with lower sensitization, whereas non-consumption was associated with lower allergy prevalence, highlighting the potential role of early feeding practices in allergy prevention.