Additional information to the Research Letter "Diet diversity in pregnancy and early allergic manifestations in the offspring", published in Clinical & Experimental Allergy. The file contains the following information: Additional information Description Page Methods Comprehensive information about the study population and methods used in the study 1-3 Fig 1 Flow chart of inclusion and exclusion of study participants 4 Table 1 List of foods included in the diet diversity score and description on how the score was calculated 5 Table 2 Data on the frequency of consumption or mean intake of the food items included in the DD score 6 Table 3 Additional results showing sensitivity analyses of the association between DD score in pregnancy and allergic manifestations until the age of 18 months presenting multivariable odds ratios additionally adjusted for post-natal factors 7