How Much Water Should You Be Drinking?

Water maintains homeostasis in the body and allows for transport of nutrients to cells and the removal and excretion of the waste products of metabolism. It also helps with regulating body temperature, cushions and lubricates joints, and protects our spinal cord and other sensitive tissues.

How Much Water Do We Need?

General recommendations are made based on average intakes of otherwise healthy people who are adequately hydrated. Individual needs can vary based on gender, weight, activity level, exposure to heat and so forth. All sources of water intake can contribute to a days worth of water including water from food sources and other fluids that contain water. About 80 percent of most individuals’ total water intake comes from drinking water and beverages, including caffeinated beverages, and the other 20 percent is derived from food.

The Institute of Medicine (IOM), through its Food and Nutrition Board (FNB), as part of the continuing activity to develop Dietary Reference Intakes (DRIs) for nutrients, undertook an 18-month study to develop DRIs for electrolytes and water.

The IOM issued a report in 2014 setting general water intake recommendations:

• Approximately 91 ounces of total water from all beverages and foods each day for women
• Approximately 125 ounces daily of total water from all beverages and foods each day for men

Staying Hydrated While Active

Some tips to reduce fluid loss through activity include:

• Drink 17-20 ounces of water two to three hours before the start of exercise.
• Drink 8 ounces of fluid 20 to 30 minutes prior to exercise or during warm-up.
• Drink 7-10 ounces of fluid every 10 to 20 minutes during exercise.
• Drink an additional 8 ounces of fluid within 30 minutes after exercising.
• Drink 16-24 ounces of fluid for every pound of body weight lost after exercise.

A Note About Sports Drinks

Many sports drinks contain large amounts of sugar, food dye, and artificial ingredients. Unless you are exercising at high intensities for prolonged periods of time, water should provide the necessary fluid replacement for exercise. Exercising for 60 minutes or more with heavy sweating may result in electrolyte loss; in which case, an additional form of fluid and electrolyte replacement may need to be considered.

Sources

• Institute of Medicine – Dietary Reference Intake for Water, Potassium, Sodium, Chloride, and Sulfate.
• Centers for Disease Control – Water: Meeting Your Daily Fluid Needs
• American Council on Exercise – Fit Facts: Healthy Hydration
• National Institutes of Health – Fluid and Electrolyte Loss and Replacement in Exercise