When should newborns be given water?

According to the World Health Organization (WHO): if your baby is exclusively breastfed for the first 6 months of life, there is no need to give them extra water (because 88% of breast milk is water, enough to provide all the water your baby needs). However, formula-fed babies can be given a few small spoonfuls of water to rinse the tongue after feeds.

When your baby reaches weaning age (6 months old), in addition to the water in porridge, soup and other complementary foods, your baby needs extra clean water. Total daily fluid, including from food, milk and plain water, is calculated by your baby's weight. Babies 1 - 10kg: 100ml per kg of body weight. Children 10 - 20kg: 1000ml + 50ml for each kg of body weight above 10kg

What you need to know about giving your baby water in the following situations
Don't give water to babies under 6 months, as milk is still their main food at this time. Giving water at this age can cause bloating and reduce how much milk your baby drinks. Also, if a newborn drinks a lot of water, there is a risk of water intoxication because it dilutes the sodium concentration in the body. Because a newborn's kidney filtration is not yet fully developed, sodium is lost from the body with the water, leading to sodium deficiency. Sodium deficiency in newborns can affect brain function. So the first symptoms of water intoxication in babies are irritability, drowsiness and other signs of changes in mental state.

If your baby is dehydrated, for example due to fever or diarrhoea, replace fluids as follows:
- Babies < 6 months who are exclusively breastfed: breastfeed as much as possible
- Babies > 6 months: give more water/milk or oral rehydration solution as directed by a doctor

Drinks you should not give your child every day.

Don't give your child fizzy drinks. Drinks with too much sugar make children thirstier, or the body has to deal with the excess sugar.

Children aged 1 - 3 can have fruit juice as a snack or light meal during the day, up to a maximum of 120ml of juice. However, don't let them drink too much, as it can cause diarrhoea or put them off their food; doctors encourage children to eat whole fruit rather than juice.

References:

The book "Feeding Young Children", Ministry of Health, Hanoi 2015