Thumb-Sucking: Can It Prevent Future Allergies? Hygiene hypothesis suggests benefit to thumb-sucking, nail-biting

Explaining the hygiene hypothesis, Jay Portnoy, MD, of Children's Hospital in Kansas City, Missouri said "Children with such habits are known to ingest bacteria that are on their hands and this is believed to protect them from developing allergies later in life." "It is possible that other factors may have played a role, but the investigators controlled for as many factors as they could think of and this did not change the results," Portnoy, who was not involved with the study, told MedPage Today via email. http://www.medpagetoday.com/Pediatrics/GeneralPediatrics/59001?xid=nl_mpt_DHE_2016-07-12&eun=g721819d0r