New research published in The Journal of Pediatrics suggests that there is no relationship and no evidence to support that long held argument that breastfeeding is a risk factor or causes severe early childhood caries.   Researchers examined the data of children between the ages of 2 and 5 who were participating in the National Health and Nutrition Examination Survey.  They established that there was no correlation between whether or not a child was breastfed and their risk of having varying levels of tooth decay.