Your body depends on water for survival. Did you know that water makes up more than half of your body weight? Every cell, tissue and organ in your body needs water to function correctly. For example, your body uses water to maintain its temperature, remove waste and lubricate joints. Water is essential for good health.
You lose water each day when you go to the bathroom, sweat, and even when you breathe. You lose water even faster when the weather is really hot, when you exercise, or if you have a fever. Vomiting and diarrhea can also lead to rapid fluid loss. If you don’t replace the water you lose, you can become dehydrated.
Symptoms of dehydration include:
Don’t wait until you notice symptoms of dehydration to act. It can be hard to recognize when you’re dehydrated, especially as you age. Actively prevent dehydration by drinking plenty of water.
There are different recommendations for water intake each day. Most people have been told they should be drinking 6 to 8 8-ounce glasses of water each day, which is a reasonable goal. However, different people need different amounts of water to stay hydrated. Most healthy people can stay well hydrated by drinking water and other fluids whenever they feel thirsty. For some people, fewer than 8 glasses may be enough. Other people may need more than 8 glasses each day.
Some people are at higher risk of dehydration, including those who get a lot of exercise, have certain medical conditions, are sick, or are not able to get enough fluids during the course of the day. Older adults are also at higher risk. As you age, your brain may be unable to sense dehydration and send the signals for thirst.
If you are concerned that you may not be drinking enough water, check your urine. If your urine is consistently colorless or light yellow, you are most likely staying well hydrated.
You may need to increase the amount of water you are drinking if you:
Water is the best option for staying hydrated. There are other drinks and foods that can help provide the water you need, but some may add extra calories from sugar to your diet.
Drinks like fruit and vegetable juices, milk and herbal teas can contribute to the amount of water you should get each day. Even caffeinated drinks, such as coffee, tea and soda, count toward your daily water intake – up to a point. But it’s best to limit these since caffeine may cause some people to urinate more frequently, or feel anxious or jittery. A moderate amount of caffeine, 200 to 300 milligrams (about the amount in 2 to 4 8-ounce cups of coffee), is not harmful for most people.
Water can also be found in fruits and vegetables, such as watermelon, tomatoes and lettuce, and in soup broths.
For most people, water is all that is needed to maintain good hydration. However, if you are planning on exercising at a high intensity for longer than an hour, a sports drink may be helpful because it contains carbohydrates that can prevent low blood sugar. A sports drink can also help replace electrolytes if you have a fever, have been vomiting or have had diarrhea.
Choose sports drinks wisely, as they are often high in calories from sugar and may contain high levels of sodium. Also check the serving size. One bottle may contain several servings. Some sports drinks contain caffeine. If you use a sports drink that contains caffeine, be careful not to get too much caffeine in your diet.
Sports drinks are not the same as energy drinks. Energy drinks usually contain large amounts of caffeine and other stimulants (for example, guarana or taurine) that your body doesn't need. Most of these drinks are also high in sugar. Many experts recommend that kids and teens should not have energy drinks.
This content was developed with general underwriting support from The Coca-Cola Company.
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Written by familydoctor.org editorial staff