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Water




Drinking water is so important for good health. When you were a kid in school, you learned that each molecule of water is made up of two hydrogen atoms and one oxygen atom. You may also have learned that it was great fun to fill up your squirt guns with water, at least until the principal caught you. What you may not have learned, however, was how much water you needed in order to be a healthy human being.

Your body is estimated to be about 60 to 70 percent water. Blood is mostly water, and your muscles, lungs, and brain all contain a lot of water. Your body needs water to regulate body temperature and to provide the means for nutrients to travel to all your organs. Water also transports oxygen to your cells, removes waste, and protects your joints and organs.

Signs of Dehydration

You lose water through urination, respiration, and by sweating. If you are very active, you lose more water than if you are sedentary. Diuretics such as caffeine pills and alcohol result in the need to drink more water because they trick your body into thinking you have more water than we need. Symptoms of mild dehydration include chronic pains in joints and muscles,lower back pain, headaches and constipation. A strong odor to your urine, along with a yellow or amber color indicates that you may not be getting enough water. Note that riboflavin, a B Vitamin, will make your urine bright yellow. Thirst is an obvious sign of dehydration and in fact, you need water long before you feel thirsty.

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How Much Water do You Need to Drink?

A good estimate is to take your body weight in pounds and divide that number in half. That gives you the number of ounces of water per day that you need to drink. For example, if you weigh 160 pounds, you should drink at least 80 ounces of water per day. If you exercise you should drink another eight ounce glass of water for every 20 minutes you are active. If you drink alcohol, you should drink at least an equal amount of water. When you are traveling on an airplane, it is good to drink eight ounces of water for every hour you are on board the plane. If you live in an arid climate, you should add another two servings per day. As you can see, your daily need for water can add up to quite a lot.

Twenty percent of your water need will come from the foods you eat. The rest of your water need should come from the beverages you drink. Water is the best choice. Sodas have a lot of sugar in them, so if you drink sodas, you may take in more calories than you need. Herbal teas that aren't diuretic are fine. Sports drinks contain electrolytes and may be beneficial, just look out for added sugar and calories that you don't need. Juices are good because they have vitamins and nutrients.

Caffeinated beverages will also add to your daily water need. Even though caffeine is a diuretic, if you regularly consume caffeine, your body will regulate itself to that diuretic effect.

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Drink Enough Water

It may be difficult to drink enough water on a busy day. Be sure you have water handy at all times by keeping a bottle for water with you when you are working, traveling, or exercising. If you get bored with plain water, add a bit of lemon or lime for a touch of flavor. There are some brands of flavored water available, but watch for extra calories.

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Water Pollution

We all need clean water. People need it to grow crops and to operate factories, and for drinking and recreation. Fish and wildlife depend on it to survive.

Many different water pollutants can harm our rivers, streams, lakes and oceans. The three most common are soil, nutrients and bacteria. Rain washes soil into streams and rivers. The soil can kill tiny animals and fish eggs. It can clog the gills of fish and block light so plants die. Nutrients, often from fertilizers, cause problems in lakes, ponds and reservoirs. Nitrogen and phosphorus make algae grow and can turn water green. Bacteria, often from sewage spills, can pollute fresh or salt water.

Water pollution is any contamination of water with chemicals or other foreign substances that are detrimental to human, plant, or animal health. These pollutants include fertilizers and pesticides from agricultural runoff; sewage and food processing waste; lead, mercury, and other heavy metals; chemical wastes from industrial discharges; and chemical contamination from hazardous waste sites. Worldwide, nearly 2 billion people drink contaminated water that could be harmful to their health.

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Factors that influence water needs

You may need to modify your total fluid intake depending on how active you are, the climate you live in, your health status, and if you're pregnant or breast-feeding.

  • Exercise. The more you exercise, the more fluid you'll need to keep your body hydrated. An extra 1 or 2 cups of water should suffice for short bouts of exercise, but intense exercise lasting more than an hour (for example, running a marathon) requires additional fluid. How much additional fluid is needed depends on how much you sweat during the exercise, but 13 to26 ounces (or about 2 to 3 cups) an hour will generally be adequate, unless the weather is exceptionally warm.

    During long bouts of intense exercise, it's best to use a sports drink that contains sodium, as this will help replace sodium lost in sweat and reduce the chances of developing hyponatremia, which can be life-threatening. Fluid also should be replaced after exercise. Drinking Water 16 ounces of fluid per pound of body weight lost during exercise is recommended.

  • Environment. Hot or humid weather can make you sweat and requires additional intake of fluid. Heated indoor air also can cause your skin to lose moisture during wintertime. Further, altitudes greater than 2,500 meters (8,200 feet) may trigger increased urination and more rapid breathing, which use up more of your fluid reserves.
  • Illnesses or health conditions. Signs of illnesses, such as fever, vomiting and diarrhea, cause your body to lose additional fluids. In these cases you should drink more water and may even need oral rehydration solutions, such as Gatorade, Powerade or Ceralyte. Certain conditions, including bladder infections or urinary tract stones, also require increased water intake. On the other hand, certain conditions such as heart failure and some types of kidney, liver and adrenal diseases may impair excretion of water and even require that you limit your fluid intake.
  • Pregnancy or breast-feeding. Women who are expecting or breast-feeding need additional fluids to stay hydrated. Large amounts of fluid are lost especially when nursing. The Institute of Medicine recommends that pregnant women drink 2.4 liters (about 10 cups) of fluids daily and women who breast-feed consume 3.0 liters (about 12.5 cups) of fluids a day.
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Staying Safely Hydrated

It's generally not a good idea to use thirst alone as a guide for when to drink. By the time one becomes thirsty, it is possible to already be slightly dehydrated. Further, be aware that as you get older your body is less able to sense dehydration and send your brain signals of thirst. Excessive thirst and increased urination can be signs of a more serious medical condition. Talk to your doctor if you experience either.

To ward off dehydration and make sure your body has the fluids it needs, make water your beverage of choice. Nearly every healthy adult can consider the following:

  • Drink a glass of water with each meal and between each meal.
  • Hydrate before, during and after exercise.
  • Substitute sparkling water for alcoholic drinks at social gatherings.

If you drink water from a water bottle, thoroughly clean or replace the bottle often. Refill only bottles that are designed for reuse.

Though uncommon, it is possible to drink too much water. When your kidneys are unable to excrete the excess water, the electrolyte (mineral) content of the blood is diluted, resulting in a condition called hyponatremia (low sodium levels in the blood). Endurance athletes - such as marathon runners - who drink large amounts of water are at higher risk of hyponatremia. In general, though, drinking too much water is rare in healthy adults who consume an average American diet.

If you're concerned about your fluid intake, check with your doctor or a registered dietitian. He or she can help you determine the amount of water that's best for you.

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Information obtained from National Institute of Health
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