Breastfeeding and Tooth Decay

Breastfeeding and Tooth Decay – Is There a Link?

Until recently, we believed that breastfeeding (mostly sleeping with the baby at night) would cause tooth decay, similar to allowing the baby to sleep through the night with a bottle of milk can cause “baby bottle mouth” also known as “Baby Bottle Caries”. Recent studies reveal this concept is no longer true during nighttime or any other time.

Dr. Brian Palmer and Dr. Harold Torney, both dentists, completed extensive research on human skulls ranging from 500 to1000 years ago.  Their study of tooth decay in children revealed that in this era before the use of baby bottles, dental decay in baby teeth was rare. These children were breastfed exclusively and most likely for a prolonged period. Their research along with others has caused them to deduce that breastfeeding is not a source for tooth decay.

Bottles at nighttime containing milk or fruit juices causes tooth decay due to the pooling of the liquid in baby’s mouth (where the liquid bathes the teeth for an extended period). Breast milk does not pool in the baby’s mouth similar to bottled milk because there is no flow unless the baby is actively sucking. Additionally, milk from the breast comes in the baby’s mouth behind the teeth. When the baby is actively suckling a synchronized swallowing occurs, therefore pooling breast milk in the baby’s mouth is unlikely.

The bacteria present in all adult mouths called strep mutans is the cause of tooth decay. These bacteria ferment the sugars in our food to produce acid that is the cause of tooth decay. Strep mutans flourishes in a mishmash of sugars, low presence of saliva and low ph. levels in the saliva. Approximately 20% of the population has elevated levels of these high acid producing bacteria and consequently, they are at higher risk for developing tooth decay. After the eruption of your baby’s teeth, these bacteria establish themselves through saliva-to-saliva contact from Mom, Dad, siblings or other caregiver. Preventing transfer of these bacteria to baby requires attention to avoiding any saliva-to-saliva contact by sharing spoons and cups, wet kisses on the mouth, pre-chewing food for baby or placing the baby’s pacifier in your mouth. There is evidence that children of mothers with high levels of strep mutans may essentially have some immunological protection from the action of strep mutans through recurrent saliva-to-saliva contact during the months prior to baby’s first erupted teeth.

Dr. Brian Palmer states in his paper that, “Human milk alone does not cause dental caries. Infants exclusively breastfed are not immune to decay due to other factors that influence the infant’s risk for tooth decay. Decay causing bacteria (streptococcus mutans) is transmitted to the infant by way of parents, caregivers, and others” (Palmer 2002).

Prior to Palmer, et. al, the only studies performed were on the effects of lactose, a milk sugar, which breast milk does contain, on teeth and not full breast milk containing all its components. Breast milk contains lactoferrin, a protein that has antimicrobial activity (bactericide, fungicide) that kills strep mutans.  The March/April 1999 issue of Pediatric Dentistry stated, “It is concluded that human breast milk is not cariogenic.” This study utilized extracted teeth to obtain most of its results and studied children only for determining the pH changes in dental plaque (Erickson 1999). A Finnish study could not find any correlation between caries and breastfeeding among children who were breastfed longer (up to 34 months) (Alaluusua 1990). Valaitis et al concluded from their studies, “In a systematic review of the research on early childhood caries, methodology, variables, definitions, and risk factors have not been consistently evaluated. There is not a constant or strong relationship between breastfeeding and the development of dental caries. There is no right time to stop breastfeeding, and mothers should be encouraged to breastfeed as long as they wish.” (Valaitis 2000).

Dr. Torney’s research found no correlation between early onset (< 2 years) dental caries and breastfeeding patterns such as frequent night feeds, feeding to sleep, etc. He concluded that under ordinary circumstances, the antibodies in breast milk destroy the oral bacteria causing decay. In the presence of small defects in the enamel (which may occur during development), the teeth become more susceptible to breakdown and the protective effect of breast milk may not be sufficient to counteract the combined effect of the bacteria and the sugars in the milk. He based his findings upon a large study of long-term breastfed children with and without caries.

From these outcomes, we can conclude that a baby who is exclusively breast-fed (no supplemental bottles, juice, or solids) unless he is genetically predisposed, will not have decay. The baby that has a genetic enamel defect may have greater decay if weaned too soon due to the lack of lactoferrin.

The other foods in baby’s diet and not breast milk that are responsible for supporting the tooth decay process. The P.R. Erickson study Investigation of the role of human breast milk in caries development. Pediatric Dent 1999 (healthy teeth were placed in different solutions) indicated that breast milk alone was virtually identical to water and found not to cause tooth decay.  Another experiment demonstrated that the teeth became stronger when immersed in breast milk, but after a small amount of sugar was added to the breast milk, the mixture became greater than a sugar solution in terms of causing tooth decay. This study stresses the importance of tooth brushing and good dental hygiene not only for our babies, but for all of us.

From the above, one can understand that beginning the routine of brushing twice per day, after your baby’s first tooth has erupted, is a wise routine to establish. Allowing your child to carry a cup or a bottle around during the day results in a continuous “bathing” of the teeth with the liquid contents. The extent of decay is directly related to the amount of time of a sucrose substance is in contact with the teeth. Avoid too many sugary, sticky foods as well and be sure to use fluoridated toothpaste.  If you have questions regarding this topic or any other dental subject, call Dr. LaMarche at (425) 357-1818