Newborn Babies Feeding What is the 4 Day Wait Rule? Share Pin Email More in Newborn Babies Feeding Health and Safety Welcoming Baby Home Baby Names Baby Milestones Sleeping Living With Baby Growth and Development Formula Feeding Homemade Baby Food Car Seat Safety Holidays with Baby Photography Tips Baby's First Birthday View All Updated April 22, 2016 The 4-day wait rule is about introducing your baby to new foods to learn about what they may be allergic to. We'll teach you more about it and what foods to avoid to early on. Up Next Up Next Article Do You Know About This Food Allergy Update? Up Next Video How to Make Beets Puree Up Next Video Best Finger Foods for Baby Up Next Article What Are the Most Common Food Allergies for Babies?