Water is necessary for carrying nutrients to your cells, flushing bacteria from your system, preventing dehydration, and replacing fluids lost from sweating, but you may not need to drink as much as you thought.
Stephen R. Daniels. pediatrician. No. You shouldn't give your newborn water or sugar water. And if you're feeding powdered or concentrated formula to your baby, never dilute it with more than the amount of water called for on the label. Your infant will get all the necessary hydration from breast milk or formula.
Water can interfere with a young baby's ability to absorb the nutrients in breast milk or formula and, because it can make her feel full, it may prevent her from feeding as much as she should.