When can babies drink water and how to offer it

Drinking enough water is essential for optimal health and well-being. Babies have the largest percentage of body water, about 78% at birth [1]. By 1 year of age, that amount drops to about 65%. 

But what does this mean for babies? Should they be drinking water throughout the day like the rest of us? The answer is — it depends! Keep reading to find out when it is appropriate to start offering your baby water and how much they need.

IN THIS ARTICLE:

Why is it important for babies to drink water?

When can I introduce water to my baby?

Why can’t babies under 6 months have water?

How much water should babies drink?

How should I offer water to baby?

What are signs of dehydration in babies?

Takeaway

Water for babies FAQ

Why is it important for babies to drink water?

Drinking water is important for everyone, including babies, since it has so many vital functions in the body. Water helps to carry nutrients throughout the body, lubricate joints, and regulate digestion and body temperature. As adults, we usually think of meeting our water needs by assessing the amount of water we drink each day. However, babies meet their needs a little bit differently. More on that below!

The American Academy of Pediatrics recommends introducing water for babies from the age of 6 months [2], although breastmilk or formula will remain their main beverage until they reach 1 year. After that, water is the best-choice beverage alongside plain cow’s or nondairy milk.

When can I introduce water to my baby?

Babies can begin to have small amounts of water when they start solids at around 6 months of age. Offer a few sips of water from an open cup or straw cup at mealtimes. Any water your baby drinks at this age is meant to get them used to its taste and introduce the skills needed for cup drinking. No need to worry if your baby doesn’t like water at first. It is not intended to replace breastmilk or formula, which still provides all the water your baby needs.

Why can’t babies under 6 months have water?

Babies younger than 6 months should not be offered water or other liquids beside breastmilk or formula. Breastmilk or formula provides sufficient water for newborns and babies up to 6 months old, even on hot days. Introducing water too early or diluting formula or breastmilk with water can be dangerous for your baby because it affects the balance of electrolytes in the blood [3] and can lead to seizures.

How much water should babies drink?

Water needs may vary quite a bit from baby to baby as well as from day to day. Factors such as the weather and activity level can impact hydration needs. Additionally, high water-containing foods such as fruit, vegetables, and soup can also contribute to water intake. 

The best way to know if your baby is adequately hydrated is to watch their diapers. Babies should have at least 6 wet diapers a day to indicate they are adequately hydrated. If you aren’t seeing that, watch for other signs of dehydration and talk to your baby’s pediatrician. 

Use the table below as a general guide, and visit Healthy Drinks, Healthy Kids for more expert information from leading health organizations, such as the American Academy of Pediatrics, the Academy of Nutrition and Dietetics, and the American Heart Association.

0 - 6 months	6 - 12 months	12 - 24 months
None	4 - 8 oz	8 - 32 oz
Breastmilk and/or formula provide enough fluids.	Serve a small amount at mealtimes once solids are introduced.	Serve at meals and snacks, as well as throughout the day.

How should I offer water to baby?

• At meals and snacks

Start by offering your baby small amounts of water at meals and snacks. This allows your baby to get used to the taste of plain water and start developing cup-drinking skills. It’s best to keep water to about 1 - 2 oz at a time, so it doesn’t displace breastmilk or formula. Stay with the lower end of the range until your baby is taking larger meals.

• In a cup

Offering water in a cup helps babies build lifelong skills such as drinking from a cup or straw. Make sure to choose appropriately-sized cups — they need to fit into small hands — and don’t be afraid to help them! Start with small amounts of water and work your way up as baby masters drinking from a cup.

• Consider foods

Fruits, vegetables, and anything that is liquid at room temperature, like soup or popsicles, all contribute to your baby’s overall water intake. Sometimes it may feel like your baby isn’t consuming a lot of liquid, but when you also take a look at their food intake, you may realize they are getting more than it appears. 

• In a smoothie or popsicle 

Making smoothies or popsicles at home is a fun way to offer water as well as to try new fruits and vegetables. They can be especially useful for babies who need extra calories or nutrients because you can pack a lot in a small amount of volume. 

• Throughout the day 

When your baby turns 1 year old, you can begin to have water available more frequently throughout the day. Place a cup out in the kitchen or playroom and let them know they can drink as needed. 

What are signs of dehydration in babies?

Dehydration can be dangerous for a baby and severe cases may require hospitalization. If you suspect your baby might be showing signs of dehydration, it’s best to call your pediatrician right away so they can guide you on what’s best to do. 

Note: Conditions such as fever, vomiting, and diarrhea put your baby at increased risk for dehydration.

According to the American Academy of Pediatrics [4], the following are signs of dehydration:

Mild to moderate dehydration:

• Less activity than usual

• Less than six wet diapers a day 

• Less saliva or cracked lips

• Fewer tears when crying

• Sunken soft spot on the head

Severe dehydration (all the symptoms listed above, plus):

• Very fussy or overly sleepy

• Sunken eyes

• Cool, discolored hands and feet

• Wrinkled skin 

• Only 1 or 2 wet diapers in 24 hours

• Dry tongue and mouth

• No tears when crying

When should I introduce a cup?

Babies can begin using a cup at about 6 months when they start to eat solids. Most feeding experts recommend starting with an open cup or a straw cup as these help to strengthen the muscles used for eating and chewing. You may also use another sippy cup as well. Babies will continue to develop their cup-drinking skills through to toddlerhood.

Takeaway

• Babies have a higher percentage of body water at birth (about 78%) which decreases to 65% by 1 year.

• Introduce water for babies around 6 months when starting solids, but breastmilk/formula remains their primary beverage until 1 year.

• Babies under 6 months shouldn't be given water.

• Water intake varies; offer small amounts (1 - 2 oz) at meals, encourage cup use, consider water-rich foods, and have water available after 1 year.

• Signs of dehydration include reduced activity, wet diapers, dry mouth, sunken eyes, fussiness, and more.

• Introduce cups around 6 months, starting with open or straw cups.