Appendix 1.

Search strategy

Search strategy	Number of references
PubMed: (asthma[TIAB] OR wheezing[TIAB] OR wheeze[TIAB] OR lung function[TIAB]) AND (diet[TIAB] OR dietary[TIAB] OR food pattern[TIAB]) Limit: Species (Human)	1,307
Scopus: ((TITLE({asthma}) OR ABS({asthma})) OR (TITLE({wheezing}) OR ABS({wheezing})) OR (TITLE({wheeze}) OR ABS({wheeze})) OR (TITLE({lung function}) OR ABS({lung function}))) AND ((TITLE({diet}) OR ABS({diet})) OR (TITLE({dietary}) OR ABS({dietary})) OR (TITLE({food pattern}) OR ABS({food pattern}))) Limit: Subject Area (Medicine; Immunology and Microbiology; Agricultural and Biological Sciences; Nursing; Pharmacology, Toxicology and Pharmaceutics; Health Professions; Environmental Science; Social Science; Multidisciplinary) and Document Type (article; conference paper)	1,272
ISI Web of Knowledge: TS=(“asthma” OR “wheezing” OR “wheeze” OR “lung function”) AND TS=(“diet” OR “dietary” OR “food pattern”) Limit: Web of Science Categories (Allergy; Immunology; Respiratory System; Nutrition Dietetics; Pediatrics; Medicine General Internal; Public Environmental Occupational Health; Critical Care Medicine) and Document Type (article; proceedings paper; meeting abstract)	1,195