evidence: 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. [...] Babies under 6 months shouldn't be given water. [...] Yes, babies can have too much water, and those under 6 months are at an increased risk. Once babies are eating solid foods, it is rare, but it can happen. You can avoid water intoxication in babies by following proper guidelines for introducing water and giving them an age- and activity-appropriate amount. Additionally, do not dilute formula or breastmilk with water.