When can babies drink water, and how much?

What does the evidence say about water for babies?

1. For a healthy infant under six months, routine extra water is not recommended. If feeding seems inadequate or the baby may be dehydrated, contact the pediatric team instead of filling the gap with water. Medical advice for a particular illness can differ from everyday feeding. 1
2. CDC lists four to eight ounces of water daily as an option between six and twelve months, alongside breast milk or formula. This is a small complementary amount, not a requirement to make a reluctant baby finish a cup or a substitute for the calories in milk. 2
3. Water used to mix formula has a separate job. Measure the exact water volume in the product instructions before adding powder. Extra dilution can leave the formula nutritionally inadequate; too little water increases the burden on the infant’s kidneys and can contribute to dehydration. 3
4. Water does not need flavoring to be useful. Infants and young children should avoid sweetened drinks, and juice is not recommended before twelve months. Honey is also unsuitable before the first birthday, including when added to water. 4
5. During a water advisory, identify the type of hazard. Boiling can address some germs but does not remove harmful chemicals or toxins. Follow local public-health instructions and the infant-feeding plan rather than assuming that boiled or filtered water is always suitable. 3

How should a baby’s water intake change?

• Before six months, use breast milk or correctly prepared infant formula for routine fluid needs unless the clinician gives different medical instructions.
• As complementary foods begin, offer small amounts of plain water in a suitable cup. Keep milk feeds central to the diet.
• Through the first year, discuss intake concerns using feeding, wet diapers and growth together. An ill or poorly feeding baby needs assessment rather than a larger water target.