It may seem intuitive to give babies water from the get-go, but there are actually a few things to know before baby starts sipping H20. 

Being a mom is funny. (Though not always ha-ha funny.) There are all these questions you’ve never had to think about––or things you totally forgot about––until one day you’re holding a squishy, squirmy baby and it dawns on you: How many layers should the baby wear when it's cold outside? When can they wear sunscreen? Oh, and water! When should I be giving them water?! Thankfully, there are some cut and dry rules (no pun intended) about when babies should start drinking water.

In this article we'll cover: 

• Why water isn’t necessary for newborns
• When babies can drink water
• Signs of dehydration in babies
  
• Ways to keep baby hydrated without water

Why Water isn’t Necessary for Newborns and Young Babies

It might seem strange that newborns don’t drink water––that’s what adults do when we’re thirsty, after all!––but there are actually several reasons why an infant’s developing system isn’t quite ready for H2O.

Breast Milk and Formula are the Primary Hydration Sources

The American Academy of Pediatrics advises that from birth to six months old, the only source of hydration babies need is breastmilk or formula. Jam-packed with nutrients and adequate calories, these liquids are enough to satiate a baby’s small, but growing, stomach. If you’re pumping, a wearable pump is an easy and convenient way to make sure baby always has a nutrient source on hand.

What are the Risks of Giving My Baby Water Too Early?

There are two major concerns with giving babies water too early. The first is nutrient dilution, or replacing their primary source of nutrition (breastmilk or formula) with water (a non-nutrient source). Because formula and breastmilk are your baby’s only sources of calories, it’s important that the liquid they consume is full of all the fat, protein, and carbohydrates they need to grow.

The next concern is water intoxication. Water can create an imbalance in the body’s concentration of serum electrolytes (think: sodium, calcium, and potassium), and anyone who consumes too much water can suffer from this. Babies, in particular though, are sensitive to decreased sodium levels. Water intoxication could lead to seizures, brain damage, coma, or death. Signs to watch out for are confusion, drowsiness, muscle twitching, nausea and vomiting, difficult breathing, and weakness. If you witness any of these in your infant, call your doctor immediately.

When Can Babies Safely Start Drinking Water?

There’s no need to panic if your baby accidentally swallows some bath water or snags a drink from his sister’s sippy cup. But when it comes to actively serving your baby water, there are thankfully a few hard and fast guidelines. 

Hello, Solids! Hello, Water!

Around your baby’s six-month mark (sometimes as early as four or five months), your pediatrician will likely recommend introducing solids. This is an optimal time to introduce water. Drinking water with solids can help prevent constipation, aid digestion, normalize blood pressure, and regulate body temperature. 

You can offer your child any kind of safe drinking water, including bottled, filtered, well, or public water––but definitely not carbonated water. Small amounts of water can also be integrated into baby’s first foods. Some parents choose to introduce babies to food with rice cereal, which can be mixed with breastmilk, formula, or water.

How Much Water to Give

The recommended amount of water per day for a six month old is up to four ounces. Some experts will advise no more than four ounces between six to nine months, while others may suggest up to eight ounces is adequate if your child is growing at a healthy rate and is not at risk for nutrient dilution.

Between bottles or nursing sessions, babies can begin intermittently taking small sips of water between meals. At mealtime, when your baby is exploring new solid foods and various textures, offer a small cup of water so they can acclimate to this routine! You can offer water in an open cup or a cup with a straw.

How Can I Tell If My Baby Is Dehydrated?

Mother to mother, our wish for you is that your feeding experience is drama free and your precious bundle thrives from Day 1. However, sh*t happens. Thankfully, there are a few telltale signs of dehydration, and as long as you’re keeping an eye on your baby, this can be easily remedied.

What to Watch Out For

To ensure your baby is getting enough breastmilk and formula, you’ll want to keep an eye on their wet diapers. At six months old, babies should have around 6–8 wet diapers a day. If your baby has significantly fewer wet diapers than this, or if their urine appears dark yellow or highly concentrated, this could be cause for concern.

Signs of severe dehydration in babies include lethargy, irritability, or crying without tears; a sunken fontanelle or sunken eyes; as well as dry skin, cold hands or feet, and rapid heartbeat. If you suspect your baby is dehydrated, seek medical care immediately.

Keeping Babies Hydrated Without Water

The rules are pretty straightforward when it comes to water and babies: No water before six months of age, and after that, only offer water at mealtimes with sips in between. If you’re concerned about baby’s hydration levels, consider offering them more breastmilk or formula. Whether nursing, pumping, or both, there are ways to try and increase your supply.

Occasionally, a situation will arise that calls for added hydration, like exceptionally hot weather or illness. In such cases, continue to offer breastmilk and formula per usual, as this will continue to be baby’s primary mode of hydration and nutrition. Avoid giving babies under 12 months old excessive amounts of water, but instead continue to offer it in sips alongside usual meals. Also stay away from juices, and contact your pediatrician if you feel additional care is needed.

Willow offers a multitude of supporting accessories to meet breastfeeding and pumping moms where they are on their journey. Whether it's breast milk storage bags, a dedicated milk pitcher, or an on-the-go cooler, there are multiple ways mom can safely store milk when she wants to stash extra output.

Your Role: Support Healthy Hydration for Babies

With new babies come new milestones, guidelines, and healthy habits to remember, and we know it can feel overwhelming to add one more thing to that list. But when it comes to water and babies, know this:

• From birth to six months (or the start of solids), babies only need breastmilk and/or formula as their source of nutrition and hydration

• After six months, its optional to offer anywhere from four to eight ounces of water a day, though breastmilk and formula will remain primary sources of nutrition and hydration until 12 months

• Always follow medical advice as it pertains to your child and consult with your doctor immediately if you have concerns about baby’s hydration or health

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FAQs

• Can newborns drink water?
  No, newborns don’t need water. Both breast milk and formula provide all the hydration a newborn needs. Introducing water too early can interfere with the baby’s nutrient intake and pose risks like water intoxication.
  

• When can I start giving my baby water?
  It’s generally safe to introduce small amounts of water to babies around six months, especially as they start eating solid foods. Always consult with your pediatrician before introducing new liquids or foods.
  

• Why shouldn’t I give my baby water before six months?
  Giving water before six months can dilute essential nutrients, disrupt digestion, and, in severe cases, cause water intoxication. Babies get all necessary hydration from breast milk or formula alone in those early months.

• How much water should I give my baby once they’re six months old?
  Start with small sips during meals, about 2-4 ounces per day, as your baby begins eating solids. Avoid giving too much water as it can fill them up and reduce their interest in more nutritious foods or breast milk.
  

• What signs indicate my baby is getting enough hydration?
  Regular wet diapers, alertness, and an active demeanor typically indicate good hydration. If you're unsure, consult your pediatrician, who can help you monitor hydration levels based on your baby's specific needs.