This may sound like weird science, but parents who suck their child's pacific to clean it may actually reduce that child's risk of developing allergies. Swedish researchers followed 184 full-term infants. At 18 months children whose parents cleaned the pacifier by sucking on it had significantly less asthma and eczema compared to those whose parents cleaned the pacifier in other ways. At 36 months they still had less eczema but not asthma. Exposure of infants to parental saliva may reduce allergies by beneficially influencing the child's microbiota.
PositiveTip: Go ahead and suck on your child's pacifier–it may reduce future allergies.