While some studies [44,45,46,47] but not all [48,49] propose that introduction of allergenic solid food from 3–4 months of age is safe and may lead to tolerance and protection against IgE-mediated food allergy, associations between solid food introduction prior to 4 months, faster infant growth and childhood obesity have been reported [50,51,52,53,54]. This evidence concerns the gene IGHE and food allergy.