How Much Water Should You Drink a Day?

Americans do not lack for beverage choices these days, but it’s hard to beat the health benefits of water and the pleasure of drinking great-tasting H2O.

Yet, you wouldn’t be alone if you ask yourself, “How much water should I drink in a day?” Is 64 ounces of water enough, for example? Is a daily gallon of water (128 ounces) too much?

How Much to Drink: Commonly Referenced Guidelines

As a starting point, consider general recommendations that The National Academies of Sciences, Engineering, and Medicine set for daily water intake for healthy, sedentary people in temperate climates: about 91 ounces (11.5 cups) of water for women and about 125 ounces (15.5 cups) for men.

The researchers say we can meet our hydration targets through many sources, which is why they focus on daily water intake instead of recommending a specific amount of drinking water.

They found, for example, that about 80 percent of people’s total water consumption comes from drinking water and other beverages, including caffeinated drinks. That means drinking coffee, tea, fruit juices, soda and milk can also count toward your daily amount of fluids—though you should always be mindful of the amount of caffeine, sugar and fat content you consume.

The other 20 percent of our daily water intake tends to come from food. Many fruits and vegetables have high water content, including watermelon, lettuce, spinach, grapes and cucumbers. While it may not be obvious, a number of dairy products contain a lot of water too, such as cottage cheese and yogurt.

Determining Your Personal Consumption Needs

Drinking when you’re thirsty can be a useful guide for how much water you should drink a day, but there are other factors to consider as well.

You may need additional water if you’re losing more fluid than usual through sweat, like while exercising or outside on a hot or humid day. You may also need to up your intake if you’re outside in cold, drying air and at high altitudes. Pregnant and breastfeeding women as well as older adults often require more water, and so do folks who are sick and losing fluids through vomiting and diarrhea.

Could drinking too much water in a day be a problem? Overhydration is possible, and people with kidneys that don’t excrete urine normally are susceptible, such as those with disorders of the heart, kidneys or liver, according to the Merck Manual. The publication adds that some antidepressants and other drugs can also cause people to drink too much water.

If you’re healthy, drinking too many fluids shouldn’t be something to worry about.  A young adult with normal kidney function would have to regularly drink more than six gallons of water a day to exceed their body’s ability to excrete water, according to Merck Manuals.

There are a number of hydration apps that can help you determine your daily water intake goals and keep track of your progress.

Ultimately, consulting with your doctor or dietician is the best way to figure out how much water you should drink based on your weight, overall health and other considerations.

Benefits of Drinking Water

Being proactive about fluid intake is important for so many reasons. Water makes up about 60 percent of our body and is critical for helping it function normally. The Centers for Disease Control and Prevention (CDC) says water removes wastes through urination, perspiration and bowel movements; keeps our body temperature normal; lubricates and cushions joints; and protects sensitive tissues like your spinal cord.

The natural beverage can also help you maintain a strong immune system, boost your energy level, and potentially even help you lose weight.

Meanwhile, we risk dehydration when we don’t replenish the water we naturally lose each day. The unpleasant condition can cause headaches, dizziness and other issues in its mildest form and more serious problems if it gets severe.

Being thirsty can be a sign you need more water, but it’s not always a symptom of dehydration. Pay attention to the color of your urine: A lack of color or light yellow are ideal, while a dark color can signal it’s time to drink up.

Drinking enough water and eating water-rich foods shouldn’t be a burden. Making sure you always have fresh, great-tasting water easily at hand can help. Consider home water filtration options like a reverse osmosis system, which can provide cleaner, safer water right from the tap. Grab a reusable water bottle—they’re status symbols now—and create menus with a variety of fruits and vegetables to make water a regular part of your day and an investment in your good health.