We often get asked not only about babies starting solids but also about how & when to keep babies hydrated.
The rule of thumb is babies do not need additional water until they are ready to wean (the NHS advises this should be at 6 months) as their kidneys aren’t yet matured. Therefore giving them too much water causes their bodies to release the excess water along with precious electrolytes & sodium.
It is believed breast milk or formula are all they require at this point to keep them hydrated – unless they have been exposed to excess heat in which case we would recommend consulting your paediatrician.
If babies are in this pre-weaning stage tap water MUST be pre-boiled and allowed to cool to make up formula. The same applies to home filtered water & bottled water as none of them are sterile.
If aboard, boiled bottled water may be used to prepare formula but be careful of the mineral content. Look for sodium (also written as Na) levels less than 200 mg per litre & sulphate (also written as SO or SO4) content shouldn’t be higher than 250mg per litre.
Once weaning starts we advise offering small sips of tap, filtered or low mineral bottled water from a beaker with meals. This is in addition to their normal milk feeds.
Look for a beaker with a free flow lid as this helps babies learn to sip rather than suck. Beakers are preferable to bottles as you know water is being drunk for thirst rather than comfort.
At this point if your baby is starting to experiment with solids sterilisation of water is no longer necessary.
As always, if you have any questions please get in touch firstname.lastname@example.org.