Drink Water

As we age, our thirst response is blunted. As a result, many older Americans may not be drinking enough water and may be at risk for dehydration, according to a report in the American Journal of Nursing (Volume 106, page 40).

Water is an essential nutrient because it is involved in all the processes in your body. Since water needs vary with diet, physical activity, environmental temperature, and other factors, it is difficult to pin down an exact water requirement. Changes in the body that accompany aging can make you vulnerable to shifts in water balance. In fact, when 35 nursing home residents were followed for six months, a third of them were found to be dehydrated -- they had not drunk enough water and other liquids, had lost too much fluid, or both.

Potential consequences of dehydration include constipation, falls, drug toxicity, urinary tract infections, longer healing times for wounds, and even hospitalization. The cue to drink, known as the thirst response, is blunted with age. At the same time, the body uses water less efficiently as we get older. Certain medications (such as diuretics and laxatives), cognitive impairment, and many illnesses (including diabetes, cancer, heart disease, and infections) also raise the odds of dehydration.

Water is a great liquid to consume, but you can also obtain fluids from fruit juices, low-sodium soups, decaffeinated coffee and tea, and water-rich fruits (watermelon, berries, and grapes) and vegetables (tomatoes and lettuce). The Institute of Medicine recommends about 11.5 cups of fluid a day for women and 15.5 cups for men, which includes water in food. (About a fifth of your fluid intake comes from food.) This doesn’t mean you should start measuring your fluid intake. Instead, the Institute says you can meet your water needs simply by drinking water and other liquids when you’re thirsty.

John's Hopkins Health Alert 10/31/07