Advice from the World Health Organization
Many people, probably including your mother, mother-in-law, nurses or even doctor may advise you to give your newborn some plain water to drink. They think this is good for your newborn’s health.
But they are not right.
According to world health organization, the newborn should be exclusively breastfed in the first 6 months of life, no water should be given to the newborn.
Even for formula-fed baby, no water should be given to him or her during the first 6 months until solid food is introduced to him or her. Also, you should never dilute the formula milk if your baby is on formula milk.
This is because breast milk or formula milk can provide necessary hydration for your newborn.
Why water can actually harm your newborn?
First, plain water or sugar water interfere with your newborn's ability to absorb the nutrients in breast milk or formula as water can make the newborn feel full, this prevent him or her from absorbing as much nutrient as she or he should. If done regularly, this can cause weight loss of your newborn, and in the case of breast-fed babies, it can decrease nursing mother’s breast-milk supply.
Furthermore, giving water to an infant can also cause water intoxication. This is a serious condition that happens when too much water dilutes the concentration of sodium in the body, disrupting the electrolyte balance and causing tissues to swell. Although it is very uncommon for this to happen, but once happen, it can be very serious, potentially causing seizures and even a coma.
What if my newborn needs extra hydration?
If your baby needs more hydration, the pediatrician may recommend an electrolyte drink. Names of the drink usually end with “lyte”.
In some rare cases, the pediatrician may recommend you to give your newborn some plain water if he or she suffers from constipation.
When to give baby water?
Most pediatricians suggest that you wait until you introduce supplementary food to your baby. This usually happen when your baby is between four and six months old.