I was prompted to research and write this article after having been told by an oral health advisor that I ought to stop breastfeeding my baby at night ‘particularly now she is on solids’ in order to prevent her developing any dental caries (tooth decay). It didn’t make sense to me that my baby would reach an age when she would suddenly start developing dental caries if breastfed at night when there are no guidelines about not feeding babies at night before they start on solids even if they have already grown teeth.
It seems to be a widely held belief that breastfeeding (particularly at night) contributes to the formation of dental caries in young children and babies. This is almost certainly not true. The myth is based on the history of bottle-fed babies developing dental caries, and it has been assumed that the situation is the same for breastfed babies, as so often seems to happen! The reason we know that dental caries cannot be blamed on breastfeeding is that pre-historic baby and toddler skeletons that have been found at the age before they would have naturally weaned from the breast, have never been found to have dental caries – the skeletons of children older than weaning age often do have dental caries.
Babies and toddlers with dental caries have been found to have extremely high numbers of a specific type of bacteria (Streptococcus Mutans) in their mouths and it is understood that it is this bacteria that is responsible for the formation of dental caries. The bacteria is not naturally present in babies’ mouths, but is passed into their mouths from other people’s saliva – usually the mother’s e.g. when she puts her finger into baby’s mouth to soothe him. It is believed that some babies are naturally more susceptible to these bacteria than others and are therefore more at risk from dental caries. The bacteria are fed by sweet/sugary things in the mouth and this is where the confusion happens. Breastmilk is sweet and therefore it is assumed that if breastmilk is in a baby or toddler’s mouth during the night e.g. during night-feeds, this will feed the bacteria and cause dental caries. However, there are several points that show that, while this is certainly the case for most sweet drinks and food, it is not the case for breastmilk:
Firstly, fluid needs to actually pool around the teeth so that they are bathed in the sugary substance in order for the bacteria to feed on it. Milk behaves differently in a baby’s mouth depending on whether or not it comes out of a breast. Milk that comes out of an artificial nipple (e.g. bottle teat) just drips slowly into the baby’s mouth even if the baby is asleep and not actively sucking so it is very easy for it to pool around the baby’s teeth. Milk that comes out of an artificial nipple also comes out close to the front of the mouth, where the teeth are located so the location of the ‘pool’ is where it could do the most damage. On the other hand, milk that comes out of a breast is drawn out by the baby actively sucking, and a baby actively suckling at the breast is also actively swallowing even if the baby is asleep so the milk is swallowed before it has a chance to pool in the mouth. In addition, if a baby is latched on well enough to be removing milk from the breast, the nipple is placed very far back in the baby’s mouth, past where the last teeth are, so even if the milk were to ‘pool’, it would not be pooling around the teeth.
Secondly, fresh breastmilk actually contains a substance, lactoferrin, which kills Streptococcus Mutans as well as two different immunoglobulins (immune factors), which slow the growth of streptococcal bacteria. There simply is no proven correlation between dental caries and breastfeeding, including long-term breastfeeding, prolonged night feeding, feeding to sleep etc. The only babies who are breastfed and develop dental caries probably have a genetic predisposition to them, and weaning from the breast may actually speed up the development of the caries due to the lack of lactoferrin and the specific immunoglobulins.
Most research that says that there is a link between breastfeeding and dental caries has been shown to be flawed. Some just looked at a few case studies, some didn’t define breastfeeding clearly and included mixed-fed babies, and some ignore other influencing factors such as fluoridation of water supply or the child’s diet other than breastfeeding.
Obviously it is important to practice good dental hygiene as well in the fight against dental caries e.g. regular teeth brushing, few sugary drinks and sticky sweet snacks etc. Other factors that can increase the risk of developing dental caries includes maternal stress during pregnancy, low intake of dairy products, medically undiagnosed illness in the mother, and antibiotics taken by the mother during pregnancy.
One last point to remind us all how totally natural practices are unlikely to be the cause of disease: The Academy of Breastfeeding Medicine stated in an article in their newsletter “It would be evolutionary suicide for breastmilk to cause decay and [some anthropologists believe] that evolution would have selected against it.”
Copyright: Clare Kirkpatrick
