Why babies under six months do not need water
In the past, when babies were fed strictly four-hourly, mothers were sometimes advised to offer boiled water if the baby was “unsettled” between feeds. Unfortunately, these babies were hungry and showing feeding cues and needed to go to the breast. Filling their tummy with warm water made them think they had been fed but they had received no calories or nutrition and were soon hungry again.
Boiled water was also suggested to bring up wind in unsettled babies. This was totally without evidence and might calm a baby signalling for more time on the breast than the clock allowed, perhaps even leading them to burp the air they swallowed from sucking at a bottle.
However, it is no longer recommended to give young babies water at all.
Both breast milk and infant formula contain the fluid babies require. Additional fluid can stress their system and even lead to water overload in extreme cases, where the kidneys struggle to process the extra fluid and natural electrolytes can become unbalanced.
In hot weather, some people worry that babies need water as well as milk. This is not the case. Breastmilk is 87% water and infant formula is around 85%. A baby who is thirsty will show feeding cues seek the breast, often for short feeds more often. Even formula fed babies can be offered extra feeds during hot weather.
Human babies survive around the world without bottles of water, as do all the other primates and mammals!
Older babies can begin drinking water as part of their introduction to family foods in the second six months, drinking from a cup. Even then, this isn't required and breastfed babies and toddlers continue to meet their fluid requirements through unrestricted breastfeeds. If mother and toddler are separated, then water from a cup is suitable for thirst. Babies under 12 months shouldn't have water in place of breastfeeds, expressed breastmilk or infant formula should still be used.
You can monitor your baby's fluid intake by continuing to check for heavy, wet nappies which are indicators that they are not dehydrated. If you are concerned, continue to offer the breast more frequently and seek medical advice if you observe signs of dehydration. You can find out more here:
