Water affects all body functions. It helps keep body temperature constant, it carries nutrients and oxygen to cells, and carries waste away. Water helps maintain blood volume and helps lubricate joints and body tissues such as those in the mouth, eyes, and nose.
The amount of water that a child needs each day may seem like a lot, but keep in mind that the suggestions include water from all sources: drinking water, other beverages and food. Fruits and vegetables have a much higher water content than other solid foods.
The daily amount of water that a child needs depends on age, weight and gender. Air temperature, humidity, activity, and a person’s overall health affect daily water requirements, too. The chart below can help you identify about how many cups of water your child or teen needs each day. These recommendations are set for healthy kids living in mild climates; therefore, they might not be exact for your child or teen.
Adapted from the Academy of Nutrition & Dietetics- https://www.eatright.org/fitness/sports-and-performance/hydrate-right/water-go-with-the-flow