Fluid Requirements for Children

Jennifer Murphy, MS, RD, LDN


So how important is water in a child’s diet? More often than not, water is the forgotten nutrient. When we think in terms of nutritional needs we tend to think about calories, protein, fat, vitamins and minerals. But what about water or any other fluid for that matter?  Adequate fluid intake is crucial in maintaining hydration status. Water, juice, or any other fluid that does not contain caffeine or alcohol can be used to maintain hydration. Water is often recommended over juice due to the high sugar content in juices. Too much juice may result in diarrhea, abdominal pain, bloating and flatulence. It also can contribute to increased dental cavities when taken by mouth.

Fluid requirements in children are based on body weight according to the Holliday-Segar method. Fluid requirements are better estimated by weight than age, to take into account the possibility of an underweight or overweight child. The table below shows the baseline requirements for a normal healthy child. It is important to note fluid requirements are higher with increased losses (i.e. fever, diarrhea, vomiting, sweating, etc.). Fluid restrictions may be required in some medical cases and those children should be carefully monitored by their physician. It is important, however, to maximize fluid intake within this restriction.

Infant formulas at standard dilution (20 calories/oz) are approximately 95 percent free water. Pediatric formulas at 30 calories/oz are approximately 85 percent free water. Free water refers to what remains after any solids are removed from a formula or food. These numbers are crucial in determining if the child is meeting his or her fluid requirement when placed on a particular formula. Water may need to be added to the tube feeding regimen depending on the total volume of the formula given daily. This may be done with water boluses, flushes to avoid clogging and water given with medications. 

Too much free water may contribute to over hydration as too little free water can lead to dehydration. Physical symptoms of dehydration may consist of weight loss greater than one percent per day, increased thirst, decreased urine output, highly concentrated urine, etc. It is always important to check with your doctor or nutritionist to determine if you are giving an appropriate amount of fluid to your child.