Breast vs Bottle

The world health organisation recommend exclusive breastfeeding for the first 6 months of life.

Issues with breastfeeding (e.g. poor milk supply, difficulty latching, discomfort or pain for the mother) can lead to inadequate nutrition for the baby.

Both breast and bottle feeding can lead to overfeeding, however overfeeding is more common in bottle-fed babies.

Breast milk contains antibodies that can help protect the neonate against infection. Breastfeeding has been linked to reduced infections in the neonatal period, better cognitive development, lower risk of certain conditions later in life and a reduced risk of sudden infant death syndrome.

Body composition appears to be slightly different between breast and bottle-fed babies and children and adolescents that were breastfed appear to have less obesity.

There is evidence that breastfeeding can reduce breast cancer and ovarian cancer risk in the mother.

It is not clear how far these benefits can be attributed to differences in socio-economic factors that contribute to a woman’s decision whether to breastfeed, and many of the claimed benefits may be due to other confounding factors.


Feeding Volumes in Babies

On formula feed, babies should receive around 150ml of milk per kg of body weight. Preterm and underweight babies may require larger volumes. This is split between feeds every 2-3 hours initially, then to 4 hours and longer between feeds. Eventually babies and infants transition to feeding on demand (when they are hungry).

Volumes are gradually increased in the first week of life as tolerated. For example:

  • 60mls/kg/day on day 1
  • 90mls/kg/day on day 2
  • 120mls/kg/day on day 3
  • 150mls/kg/day on day 4 and onwards


Initial Weight Loss in Babies

It is acceptable for breast fed babies to loose up to 10% and formula fed babies to loose up to 5% of their body weight by day 5 of life. They should be back at their birth weight by day 10. If they loose more weight than this or do not regain their birth weight by two weeks, they need admission to hospital and assessment for possible causes.

The most common cause of excessive weight loss or not regaining weight is dehydration due to under feeding, even when they do not clinically look dehydrated. The most reliable sign of dehydration in babies is weight loss.



Weaning refers to the gradual transition from milk to normal food. Weaning usually starts around 6 months of age. It starts with pureed foods that are easy to palate, swallow and digest, for example pureed fruit and “baby rice”.

Over 6 months this will progress towards a healthy diet resembling an older child, supplemented with milk and snacks to 1 year of age. 


Last updated January 2020