Drinking enough fluids is important during our hot summer weather – especially for senior citizens, according to LSU AgCenter nutritionist Dr. Beth Reames.
Hot weather can lead to body water loss, dehydration and heat stroke, Reames and other experts point out. In fact, experts in the Centers for Disease Control and Prevention report that more than 300 people die each year from heat-related illnesses.
"Even small losses of body water can impair activity and judgment," Reames says, noting that mild dehydration may result in a loss of 1 percent to 2 percent of body weight. That converts to a loss of 1.5 to 2 pounds for someone weighing 150 pounds.
Studies show senior citizens may not drink sufficient fluids. They also may be taking medications, such as diuretics for high blood pressure, which cause fluid loss. One study of healthy retirees found 8 percent with moderate dehydration and about 33 percent likely to have chronic mild dehydration.
According to the Dietary Guidelines, the combination of thirst and normal drinking patterns, especially fluids with meals, is usually sufficient to maintain normal hydration. The guidelines also state that healthy individuals who have routine access to fluids and who are not exposed to heat stress consume adequate water to meet their needs.
Reames says, however, to avoid dehydration during prolonged physical activity or when it is hot, individuals should consume fluids regularly during the activity and drink several glasses of water or other fluid after the physical activity.
In very hot weather, very active individuals may need 6 liters or more of water daily, according to several studies.
Besides physical activity and heat, other conditions affect water needs. They include diet, disease, overall health, diuretics and medications.
"It’s also important to remember that water needs vary from day to day," Reames says.
The Institute of Medicine recommends that adult women consume 2.7 liters (11 1/2 cups) of fluid daily and adult men, 3.7 liters (15 1/2 cups.) The fluid may come from a variety of sources – that is, all beverages, including water, as well as moisture in foods. High-moisture foods include watermelon, meats and soups.
Beverages and food both supply water. About 80 percent of people's total water intake comes from drinking water and beverages – including caffeinated beverages – and the other 20 percent comes from food. Solid foods may contribute about 4-5 cups of water each day. Many fruits and vegetables are 90 percent fluid.
According to a report from the Food and Nutrition Board, drinking caffeinated beverages doesn’t lead to total body water deficits. These beverages can be consumed to help meet hydration needs, along with other beverages and food.
"It’s important to drink enough fluids, especially during hot weather," Reames stresses, offering these additional tips: