Does Breastfeeding Cause Cavities?

by Sabrina Granniss, IBCLC June 24, 2022

Exclusive breastfeeding is recommended for the first 6 months of a baby’s life. Around 6 months old, complementary foods are introduced. Breast milk continues to be the main source of nutrition for a baby through their first year of life.

Fun Fact: Breastfed babies have exposure through breast milk to the variety of flavors from foods in the family’s diet.(1)

Around the middle of the first year postpartum, the baby’s teeth begin to emerge. As you anticipate the eruption of your baby’s first teeth, you are not alone in wanting to know how to keep their teeth healthy.

Baby’s primary teeth general guidelines(2)

Boys teeth may erupt later than girls
Lower front teeth (central incisors) typically come in first filled by the top front 4 teeth (upper incisors)
Teeth on the upper jaw come in about 1-2 months after the lower jaw’s teeth
The first 4 molars come in after the incisor teeth followed by the last 2 lower incisors
Cuspids or the pointed teeth followed by the 4 second molars are last to come in around age 2
There is a total of 20 primary teeth
There can be a big difference from baby to baby of when their teeth come in

Anatomy of a tooth

Crown of the tooth is the part we see and it is covered in enamel which is hard, calcified tissue that contains no living cells. If it is weakened, it can often be mineralized and repaired, but the more damage to the enamel there is, the more likely a cavity may not be able to be repaired.
Dentin is the largest part of the dental tissue, the inner layer just below the enamel. When enamel is lost, you may be more sensitive to foods that are hot, cold, acidic or sticky because they have more access to the nerves below the dentin.
Pulp is soft tissue at the center of the tooth, home to the nerves, blood vessels and connective tissue.(3)
Root - secures the tooth to the jaw

What contributes to dental cavities?

The baby’s oral pH is too acidic
Diet high in sugar and processed foods
mom’s oral health
Streptococcus mutans bacteria
oral restrictions
Dry mouth
Antibiotics and medications

Breastmilk and breastfeeding

The myths:

Breastfeeding causes dental caries.
Breastfeeding at night causes milk to pool in the baby’s mouth.
lactose in breast milk breaks down tooth enamel leading to decay.

The science:

Human milk deposits calcium and phosphorus onto the teeth’s enamel, protecting the teeth from decay.(4)
Antibacterial qualities and enzymes in human milk are protective of lactose and do not lead to tooth decay unless other foods containing sugar or carbohydrates are in the diet.
Breast milk contains lactoferrin which kills Streptococcus mutans, a bacteria that creates a biofilm of plaque on the teeth.(5) Too much plaque build up leads to dental caries.
Research shows that breast milk itself is not the cause of cavities. In fact, human milk has a similar pH as water.(4) Foods introduced into the baby’s diet that are high in sugar change the pH of saliva. When the baby’s mouth is more acidic, it breaks down their teeth’s enamel and they are more susceptible to decay.
A baby that is able to use their mouth and muscles functionally during feeding takes a large portion of areola in their mouth. When they begin to suck, the nipple lands in the back of the mouth near the hard and soft palate juncture. Milk is released in the back of the mouth to be swallowed. It doesn’t pool in the baby’s mouth unless oral function is compromised meaning there is a shallow latch, they are not able to handle the milk flow or their suck/swallow is disorganized.(6)
Human milk is how human babies have survived since the beginning of time. It doesn't make sense that breast milk would cause cavities. Without their teeth, babies would not have been able to chew their food or survive. Skulls from prehistoric times show more flattened teeth, wide broad palates and a “U” shape of the dental arches.(8) Comparing this to skulls of today, there are many more palates with a high narrow palate with crowded dental arches.
Oral restrictions decrease the range of motion the tongue has. The tongue may not be able to clean the teeth as well if it can not reach the teeth. If there is a lip tie, food is more likely to sit on the front teeth rather than be cleared and can lead to decay.(9)
Less saliva is produced at night. Breastfeeding can prevent the baby’s mouth from being dry overnight especially if they are breathing through their mouth rather than their nose. A deeper investigation with your IBCLC(International Board Certified Lactation Consultant) will help determine why they are not able to keep their lips sealed for nose breathing.
Use of antibiotics during delivery changes the baby’s oral microbiome.(11) Some medications are high in sugar. Both contribute to an environment where decay is more likely.

How to promote healthy tooth development

Avoid sugary foods and drinks, processed foods like bread and pastas that break down into sugar.
Offer vegetables like broccoli, bell peppers and leafy greens which are more alkaline and maintain a healthy oral pH(7)
Give water instead of fruit juice or any carbonated drinks that break down tooth enamel.
A diet of whole foods high in vitamins and minerals including foods like homemade broths and mineral rich nori seaweed.
Vitamin K2, D3 and A - vitamin K2 has been shown to reduce the bacteria that can change saliva and help move minerals from the saliva to the teeth, halting decay. Vitamin D3 promotes calcium absorption. Vitamin A is necessary for maintaining the proper balance of vitamin D and K.(12)
Introduce solid foods that encourage chewing which works to strengthen the jaw compared to soft foods.
Practice good oral hygiene yourself. Streptococcus mutans can be passed from parent to baby.(10)
Cell salts help the body absorb minerals from the foods we eat and promote healthy teeth, hair, skin and nails. Cell salts for healthy teeth include Silica, Calc Fluor and Cal Phos.(13)
Fluoride - there are different forms of fluoride and are either naturally occurring or synthetic. Most tooth products contain a synthetic form which is possibly toxic. Instead, focus on natural sources of fluoride to promote healthy mineralization and protection for your teeth.(14)
Avoid tooth products containing glycerin. It can coat the tooth and not allow for remineralization of teeth.