You crave a glass of water on a warm summer day or after a brisk walk. You drink some in the morning to help you feel more awake, and you have a bit with meals to help digest your food. You reach for water because, instinctively, you know how vital it is to your health. And your body helps you remember that with a little thing called thirst (when you’re paying attention to it, that is).
Over the course of the day, the average person loses one to two pints of water due to sweating, urinating and just living, as various metabolic processes in the body use water to function. When the body needs more water, thirst signals reach the brain, which prompt us to drink. Despite this, many of us find ourselves dehydrated because we aren’t in tune with this all-important message, or we aren’t getting an adequate amount of fluids to meet our needs.
It’s estimated that our bodies are made up of anywhere from 60 to 70 percent water, and we can’t live for more than a few days without it. Water is in every cell, tissue and organ, and nearly all of the major systems in the body depend on it to thrive. Staying well hydrated:
Keeps Your Bowels Healthy and Flushes Out Toxins: Water helps prevent constipation by keeping stool soft and, thus, easier to pass. It also flushes out waste products and toxins floating around your body, which get expelled in your stool, urine and sweat.
Aids Digestion: Drinking ample amounts of fluids helps dissolve minerals and other nutrients in the food you eat, making them easier to digest and more accessible to the body.
Regulates Blood Pressure and Circulation: If you’re properly hydrated, your blood volume will be optimal too, which leads to steady blood pressure and heart rate. The resulting healthy blood circulation aids in carrying nutrients and oxygen to the cells and helps flush out waste products.
Regulates Body Temperature: Being well hydrated is critical to your body’s ability to sweat, which helps dissipate heat and cool you down. If you don’t compensate for your sweat loss with enough fluids, your core body temperature will increase, which can lead to symptoms such as headaches, cramping and, in worse cases, fainting.
Maintains Good Tissue Health and Lubricates Joints: Think of your body’s organs like big sponges: Ample water moistens tissues, such as those in your mouth, eyes and nose. It also keeps your body’s joints well lubricated and cushioned.
Boosts Cognitive Function and Mood: Research shows that even mild levels of dehydration can produce disruptions in thinking and mood.
How Much Water Do You Need?
While many experts recommend drinking eight 8-oz glasses of water a day, the Institute of Medicine suggests that men take in 3.7 liters (roughly 15 cups) and women 2.7 liters (about 11 cups) a day. That may sound overwhelming, but remember that you can get some of your daily water allotment from alternative sources like herbal tea, broths and fruits and vegetables, too. Fruit juice and sports drinks are another option, although you might consider watering them down to reduce the amount of sugar you’re getting from them.
And keep in mind that these numbers are not a hard-and-fast rule: Depending on your size, your activity level, the climate you live in, how much you sweat and other factors, you may need more (or less) water.
If you’re sweating more due to physical exercise, you’ll need to up your water intake. A good rule of thumb: Drink an extra glass or two for every 30 minutes of activity. If you’re living in a warm climate or at elevation, make sure you’re drinking enough so that you don’t feel thirsty. (Altitudes greater than 8,000 feet may trigger increased urination and more rapid breathing, which use up more of your body’s fluid reserve.)
How to Stay Hydrated
Staying well hydrated requires conscious effort. In general, follow these guidelines to ensure that you’re getting enough fluids:
Drink by Schedule, Not by Thirst: If you feel thirsty, there’s a good chance you’re already dehydrated. If this happens to you often, consider implementing rituals to drink water several times a day. For example, you can decide to drink a glass with every meal, at the top of every hour or when you wake up in the morning and before you go to sleep at night (as long as this doesn’t make you wake up in the middle of the night to urinate).
Load Up On Water-Rich Foods: Don’t overlook food as a good source of hydration. It’s estimated that most of us get 80 percent of the water we need from drinking fluids and 20 percent from food. Some of the most hydrating foods are fresh, juicy fruits (such as apples, berries, coconuts, grapefruits, kiwis and watermelons) and raw, green vegetables (like bok choy, broccoli, cabbage, celery, escarole and spinach). Water-based, clear soups (think vegetable soup) are also a good food source.
Monitor Your Urine Color: The kidneys produce darker-colored urine when they don’t have adequate water, so mid- to dark-colored urine is a good sign that you need to drink more fluids. The ideal color of urine is clear or light yellow.