Diversity of complementary diet and early food allergy risk

INTRODUCTION: Diet diversity (DD) in infancy may be protective for early food allergy (FA) but there is limited knowledge about how DD incorporating consumption frequency influences FA risk. METHODS: Three measures of DD were investigated in 2060 infants at 6 and/or at 9 months of age within the NorthPop Birth Cohort Study: a weighted DD score based on intake frequency, the number of introduced foods, and the number of introduced allergenic foods. In multivariable logistic regression models based on directed acyclic graphs, associations to parentally reported physician-diagnosed FA at age 9 and 18 months were estimated, including sensitivity and stratified analyses. RESULTS: High weighted DD scores (24-31p) at age 9 months were associated with 61% decreased odds of FA at age 18 months OR (95% CI) = 0.39 0.18-0.88 compared with infants with the lowest DD scores (0-17p). The association remained significant after exclusion of early FA cases. Having introduced 13-14 foods at age 9 months, independent of consumption frequency, was associated with 45% decreased odds of FA OR (95% CI) = 0.55 (0.31-0.98) compared to having introduced 0-10 foods. When stratifying, significantly reduced odds for FA were seen for children with eczema and for children with no FA history in the family. No association was seen between DD at age 6 months and FA at age 18 months. CONCLUSION: A diverse diet at age 9 months may prevent FA at age 18 months. Our results underscore the need for additional investigations on the impact of consumption frequency in infancy.