Nutrition: Hydration Chapter 6

Staying Afloat


Every Age, Every Stage

Water the Kids

Young children have more body-surface area per pound than their parents do. Put another way, kids are dense, and therefore need more water relative to their weight than adults do. Also, since sweat glands aren’t as active before adolescence, a parent may not know just how badly a child needs a drink. On hot days, on warm car rides, and at children’s athletic events, make sure they have enough water. READ MORE

Ageless Advice

Age is just one determinant of how much water a body may need. Health experts at the Mayo Clinic have noted these additional physical and environmental factors that increase the need for fluid:

  • Increased physical activity

  • Hot and humid weather

  • Dry indoor air and high altitudes, both of which reduce moisture in the air

  • Having an illness; especially one accompanied by fever, vomiting, or diarrhea

For Mother and Child

Many factors impact an individual’s water needs, but one method for estimating a recommended intake is to base water consumption on food consumption. As a rule of thumb, every 1000 calories calls for a little more than 5 cups of water. A moderately active woman in her 20’s consuming 2000 calories should drink about 10 cups per day.

Obstetricians often suggest that women in their second trimester of pregnancy increase caloric intake by about 300 calories. In keeping with the formula above, that moderately active woman in her 20’s will now be up to 2300 calories per day, and should drink an extra 1.3 cups of water. When in doubt, err towards drinking more water.

For nursing mothers, fluid needs are especially high. The Institute of Medicine recommends women who breast-feed consume about 13 cups of fluids daily.

Change with Age: Urine Frequency

A well-hydrated adult produces about four to eight cups of urine per day. The brain gets the signal to empty the bladder once urine volume reaches about 250 milliliters (a little over one cup; a very full bladder can hold nearly twice that). But as we age, the urinary sphincter muscles at the base of bladder cannot withstand as much pressure, resulting in a more frequent urgency to urinate.

Partial or total incontinence can result in men who’ve had prostate surgery or radiation treatment for prostate cancer. If the urinary sphincter is not preserved during a procedure, there is increased risk of incontinence. LESS


Chronic Conditions: Water’s Role in Diabetes and Glaucoma

Diabetes Insipidus

Intense thirst and significant loss of fluids through urine are the hallmarks of diabetes insipidus, a rare condition in which the body cannot regulate fluid levels. The four different types of diabetes insipidus — central, nephrogenic, gestational, and dipsogenic — are each characterized by a disruption to the body’s management of antidiuretic hormone (ADH), which governs the rate of fluid excretion through the kidneys. Though the condition shares a name with diabetes mellitus (types 1 and 2), diabetes insipidus is actually unrelated. READ MORE

“The Silent Thief Of Sight”

Glaucoma, a leading cause of blindness, is caused by an increase of water-based pressure within the eye. In a healthy eye, a fluid called aqueous humor circulates from behind the iris to the front of eye and then drains through a tiny canal back into the bloodstream. But when drainage in the canal is slowed or blocked, pressure increases and damages the optic nerve. The condition is painless, but if left untreated will eventually lead to complete loss of sight. LESS


The material on this site is for informational purposes only and is not intended as medical advice. It should not be used to diagnose or treat any medical condition. Consult a licensed medical professional for the diagnosis and treatment of all medical conditions and before starting a new diet or exercise program. If you have a medical emergency, call 911 immediately.