How Many Ounces of Water Should a Person Drink in One Day?

Water keeps the body moist and hydrated and helps ensure that all body systems function properly. Every day, a person needs to consume enough water to replace what is lost through breathing, sweating and excretion of waste. Many different factors help determine how many ounces of water a person should drink in one day.

One cup of water equals 8 ounces. (Image: Jupiterimages/liquidlibrary/Getty Images)

Amount

The oft-quoted standard recommendation for how much water a person should drink in one day is at least 8 cups, or 64 ounces, according to a 2009 article published online in "Scientific American," but the actual amount required varies from individual to individual. Another guideline, from Clemson University Extension, is to drink 1 quart, or 32 ounces, of water for every 50 pounds of body weight. Factors such as diet, exercise habits and health status all affect the amount of water a person actually needs to drink in a day.

Sources

Tap water, bottled water and other fluids supply most of the water the body needs, but many foods also contain significant amounts of water and can contribute to an individual's daily requirement. Very watery foods, such as yogurt and fresh fruits and vegetables, such as watermelon, tomatoes and lettuce, contribute a significant amount of water to the diet. Milk, fruit juices, vegetable juices and other non-alcoholic and non-caffeinated beverages are also good sources of water. A person who eats a lot of watery foods doesn't have to drink as many fluids to get enough water.

Significance

No one can live more than a few days without water because every organ in the body and every bodily function depends on water. Blood and muscle tissue are made mostly of water. Water helps the body maintain a normal temperature, protects joints and carries oxygen and nutrients in the blood to cells throughout the entire body.

Recommendations

The 2005 U.S. Dietary Guidelines Advisory Committee concluded that typical drinking of fluids, especially at meals, and a normal response to the sensation of thirst, are enough to ensure that most people will stay sufficiently hydrated. While there is no official recommendation for how many ounces of water a person should drink each day, the U.S. Department of Agriculture establishes Adequate Intake (AI) amounts to be used as guidelines. The AI for women ages 19 and above is 2.7 liters or about 91 ounces a day; for men ages 19 and above, 3.7 liters or about 125 ounces a day. These figures include water from both food and beverages.

Considerations

Some people, such as infants, young children, seniors, outdoor workers and athletes, are especially prone to dehydration, according to University of Nebraska-Lincoln Extension, and must have their water intake monitored more carefully than others. To stay properly hydrated, these groups need to drink water frequently throughout the day. People of all ages who engage in outdoor physical activities, particularly in warm climates, usually need to drink more water than others.

REFERENCES & RESOURCES
Load Comments
PARTNER & LICENSEE OF THE LIVESTRONG FOUNDATION

Copyright © 2019 Leaf Group Ltd. Use of this web site constitutes acceptance of the LIVESTRONG.COM Terms of Use , Privacy Policy and Copyright Policy . The material appearing on LIVESTRONG.COM is for educational use only. It should not be used as a substitute for professional medical advice, diagnosis or treatment. LIVESTRONG is a registered trademark of the LIVESTRONG Foundation. The LIVESTRONG Foundation and LIVESTRONG.COM do not endorse any of the products or services that are advertised on the web site. Moreover, we do not select every advertiser or advertisement that appears on the web site-many of the advertisements are served by third party advertising companies.