This information has been reviewed and adapted for use in South Carolina by J. G. Hunter, HGIC Information Specialist, and K. L. Cason, Professor, State EFNEP Coordinator, Clemson University. (New 09/05.)
All beverages are mostly water, which is a nutrient that is essential to life. Every body function depends on water, and you can live only a few days without it. Your total body weight is 55-75% water, which is approximately 10 to 12 gallons. Water makes up about 83% of blood, 73% of muscles, 25 % of body fat, and 22% of bones.
Eighty percent of your total fluid intake comes from beverages of all kinds, and the other 20% comes from foods. Fruits and vegetables— fresh, frozen and canned—contain lots of water. For example, watermelons, tomatoes, lettuce and celery contain more than 90% water, and oranges are 87% water.
Milk, soymilk, juice and soup all supply water to the body and contain other nutrients.
Choose water as your primary beverage. It is usually inexpensive and readily available. Water is also thirst quenching, contains no calories, fat, cholesterol, or caffeine, and is low in sodium. Water’s other benefits include:
Tap water, especially from large municipal water systems, is just as safe as bottled water and less expensive. If bottled water gets a person to drink more water, then the added expense may be worthwhile. Be aware, however, that some bottled water is actually reprocessed tap water, and others have added sugar and sodium.
On an average day, a healthy adult needs 8 to12 cups of water to replace the amount lost through perspiration, breathing, urination, and bowel movements. These fluids must be replaced to avoid dehydration and to keep the body working normally. When eating a high fiber diet, extra water is needed to process the additional roughage.
In general, one quart of water is needed daily for every 50 pounds of body weight. The exact amount of water needed depends on: age; gender; weight; health; level of physical activity; foods eaten; any medications taken; and the weather.
Thirst is one sign that you need fluids. Your current fluid intake is probably adequate if you drink enough water to quench your thirst, you feel well, and you produce a normal amount of urine that is colorless or slightly yellow. However, do not wait until you feel thirsty before drinking something. Sometimes the brain doesn’t get the thirst signal. Older adults often lose the ability to sense thirst.
Exercise: When involved in an active sport that makes you sweat, drink plenty of water throughout the day, not just during the activity. Sweat, or perspiration, is the body’s natural way of cooling down, especially on a hot day or when your body gets a real physical workout. Without fluids, your body overheats. To replace fluid loss, drink plenty of water and juice or milk before, during, and after physical activity. These fluids prevent dehydration and the tiredness that accompanies it.
To avoid cramps and dehydration during activity, drink fluids at regular intervals, and continue to replenish with water after the activity is completed. A good rule of thumb is to drink a cup of fluid every 15 minutes during and immediately after exercise.
Drink the following amounts of fluids when exercising rigorously or in very hot weather:
—2 cups during the two hours before exercising;
—1 to 2 cups within 15 minutes of the activity;
—½ to 1 cup every 15 to 20 minutes during exercise. (One medium mouthful of fluid equals about 1 ounce, and 8 ounces equals 1 cup.)
—3 cups for each pound of body weight lost.
For most physically active people, water is the best fluid choice. Sports drinks are necessary only for endurance athletes and people who have exercised for an hour or more, because they lose sodium and potassium through sweating.
Environment: In hot or humid weather, drink additional water to replace what is lost through sweating and to help lower body temperature. In winter more fluids are required due to loss of skin moisture from heated indoor air. Extra water may be needed in cold weather if you sweat while wearing insulated clothing. High altitudes (greater than 2,500 meters or 8,200 feet) cause an increase in fluid needs, and recirculated air on planes promotes dehydration, also.
Health Conditions or Illnesses: Fever, vomiting and diarrhea cause the body to lose extra fluids that must be replaced with water or other solutions such as Gatorade. Sometimes intravenous water and electrolytes may be necessary. Certain health conditions prevent the body from getting rid of water—heart failure and diseases of the kidney, liver, adrenal and thyroid. People with urinary tract stones usually need to increase water intake.
Pregnant or Breast-Feeding: Women who are pregnant or breast-feeding need additional water. The Institute of Medicine recommends that pregnant women drink nearly 10 cups of fluids a day, and women who breast-feed should get about 13 cups of fluids daily.
*Every time you drink, bacteria from your mouth contaminate water in the bottle. Keep your water bottle clean or replace it often. Wash it in hot, soapy water or run it through a dishwasher. If you use a bottle repeatedly, make sure it is designed for reuse.
Select other drinks that have a lot of calcium, vitamin A or vitamin C. This includes milk, fortified soymilk, vegetable and fruit juices. Make healthful drink choices based on the food labeling "5-20" guide. This means that a beverage is a very good choice if it contains 20% of more Daily Value for calcium, vitamin A or vitamin C in one serving. On the other hand, 5% or less Daily Value per serving means that it is a poor choice.
Fruit & Vegetable Juices:
Limit beverages that contain caffeine and alcohol, as well as too much sugar and calories. Examples are sweet tasting liquids such as: soft drinks; tea sweetened with sugar; sports drinks; fruit juices and fruit drinks. Water and sports drinks are better choices than beverages containing caffeine, alcohol, or carbonation.
Drink Less Soft Drinks, or Sodas: Enjoy soft drinks, or sodas, in moderation. Avoid substituting them for water or calcium-rich milk. Although soft drinks are mostly water, they contain large amounts of sugar or sugar substitute and no nutrients. An average 12-ounce soft drink contains 150 calories, 9 teaspoons of sugar, and no nutritional value. Avoid diet sodas, which may promote weight gain in some people.
Follow these tips to reduce soda consumption:
Soft drinks, coffee, and tea contain caffeine, which is a mild stimulant and can act as a diuretic. This promotes fluid loss through urination and contributes to dehydration. Although caffeine has a diuretic effect, this effect may be temporary and does not lead to cumulative total body water deficits.
Drink Alcohol in Moderation: Alcoholic beverages do not count toward your daily fluid intake. They supply calories and few nutrients, while having a diuretic effect on the body. Consumption of alcoholic beverages should be limited and preferably accompanied with food. The Dietary Guidelines for Americans, 2005 recommends that adults who choose to drink alcoholic beverages should do so sensibly and in moderation. The definition of moderation for women is up to one drink on any single day, and for men it is up to two drinks per day. Drink sizes include: 12 fluid ounces of regular beer, 5 fluid ounces of wine, or 1.5 fluid ounces of 80-proof distilled spirits. Each drink contains the same amount of alcohol.
Lack of water can lead to dehydration, a condition when the body does not have enough water to carry on normal functions. Dehydration is a health risk, especially for the very young and the very old. A 20% loss of water is life-threatening. Mild dehydration over time has been linked with increased cancer risk, reduced salivary gland function, kidney stones, and even fatal heart attacks.
Thirst is the first symptom of dehydration. Fluids should be consumed before you feel thirsty.
Symptoms of Dehydration Include:
*If you are properly hydrated, urine should be clear to pale yellow. You should urinate every 2 to 3 hours.
Although it is extremely rare in healthy adults, it is possible to drink too much water. If you are concerned about drinking too much or too little water, let your doctor or a registered dietitian help you determine the amount that is best for you. See a doctor if you are always thirsty or urinate too much, because these may be signs of diabetes.
This information is supplied with the understanding that no discrimination is intended and no endorsement by the Clemson University Cooperative Extension Service is implied. All recommendations are for South Carolina conditions and may not apply to other areas. Use pesticides only according to the directions on the label. All recommendations for pesticide use are for South Carolina only and were legal at the time of publication, but the status of registration and use patterns are subject to change by action of state and federal regulatory agencies. Follow all directions, precautions and restrictions that are listed.