Babies were made to breastfeed, but most babies get a bottle at some point. Some babies only have the occasional bottle; others have several bottles daily if they are exclusively bottle-fed or while their mom is at work. Babies get milk differently from the breast vs. a bottle. Understanding the differences and some bottle background information can help you make choices that support your baby’s best feeding development and experience.
Breastfeeding vs. bottle feeding mechanics
Muscles - breastfeeding uses more muscles and jaw movements than bottle feeding.
Lips - the lips form a seal at the breast and bottle.
Tongue - the movement of the tongue during bottle feeding is piston-like compared to wave-like during breastfeeding. (1)
Milk flow- the baby needs to actively remove milk during breastfeeding. Bottle feeding is more passive. Milk flow is more constant with bottles compared to the breast, which has periods of fast flow during a milk ejection and periods of slower flow.
Milk removal - bottle feeding is achieved from suction and compression. Breastfeeding is achieved by the baby creating positive pressure, pressing the breast tissue to the roof of the mouth to compress the milk sinuses, and then creating negative pressure for milk to be removed out of the nipple.
Control - the baby controls the breastfeeding process, but the parent is more in control during bottle feeding. Be cautious of overfeeding with bottles.
Breastfeeding flow rate
When babies breastfeed, they latch deeply and use suction to draw the nipple in and back towards where the hard and soft palate meet. Using their tongue, they begin nursing, getting a few drops of milk. The beginning of sucking releases the hormone oxytocin in the parent, which sends a message to release milk, and she experiences the milk ejection reflex or milk let-down. The baby’s suck pattern changes as they get a larger bolus of milk from each suck. They will need to swallow more during this time. As milk flow slows down again, they suck a few times to create a bolus of milk before swallowing, giving them more time to breathe while they continue nursing.
Bottle flow rate
When the baby drinks from a bottle, we want them to have time to breathe, have controlled swallowing, and not be overwhelmed. During swallowing, a baby closes their airway for just that moment. The slower the bottle feeding, the more opportunity the baby has to breathe and maintain their oxygen levels while they take the bottle. How we position the baby during feeding makes a big difference. If they are in the classic cradled hold we often see in magazines, with the milk continuously flowing into their mouth, they must swallow, which means fewer opportunities for breathing.
Don’t believe the marketing! Just because a bottle is marketed as slow flow doesn’t mean it actually is. Even among the same bottle nipples, not each one has the same flow rate. (2)
In a study of 45 different nipple brands, testing 10 of each showed there is a range of flow rate from 2 mL/minute to more than 80 mL/minute. (2)
Another study of 26 different brands showed similar results with a range of 1.68 mL/min to 85.34 mL/min. (3)
Babies with great oral function and who are healthy full-term babies may not have a problem handling the fast flow from the bottle, but babies who have feeding challenges or are born prematurely may have difficulty with a bottle with a faster flow. Remember, the flow from a bottle is also continuous and should be taken into consideration when we consider how to feed a bottle.
The baby is sitting upright on the caregiver's lap, but the baby still has to be supported by the parent or caregiver
A slower way to bottle-feed
Still controlled by the parent or caregiver
Milk may still pool in the baby’s mouth
Encourages the caregiver to follow the baby’s cues
The bottle is held horizontally to the floor and tipped down or up to pause or deliver milk to the baby
It can still be tiring for the person feeding the bottle
Side-lying bottle feeding
Side-lying paced bottle feeding gives the baby more control over the feeding
A slower way to feed the baby
Reduces the pooling of milk in the baby’s mouth. Instead, excess milk will drip out the side of their mouth
More baby controlled
More closely mimics a breastfeeding position
Baby can pause as they desire during the feeding
Baby’s body is fully supported and has greater postural stability
Allows the baby to actively feed rather than passively feed
The bottle is held horizontally to the floor and can be tipped up to make milk available to the baby or down to stop milk flow when the baby pauses their suck pattern
Supports breathing and swallowing coordination
Very comfortable for the person feeding the bottle
**Check out our blog post here for step-by-step instructions on how to do side-lying bottle feeding
Going back and forth between breast & bottle
Paced bottle feeding and feeding a bottle so the baby uses their reflexes for feeding support the baby's ability to go back and forth more easily between the breast and bottle.
We still want them to open their mouth wide and take a large portion of the nipple, whether at the breast or bottle.
Placing the bottle on their chin first signals them to open their mouth wide.
Put the bottle nipple in their mouth so their lips can flange close to the base of the nipple.
Paced bottle feeding considers the mechanics of breastfeeding versus bottle feeding. It helps to understand the involvement of muscles, lip seal, and tongue movements involved in each. Breastfeeding engages more muscles and utilizes wave-like tongue movements, while bottle feeding relies on piston-like tongue movements. Additionally, the flow rate differs between breastfeeding and bottle feeding, with breastfeeding having periods of fast and slow flow, while bottle feeding offers a more constant flow. Understanding these differences can help parents make informed choices and promote successful bottle-feeding experiences for their babies.