People carry bottles of water everywhere these days, but how much hydration does a body really need?
"We used to say eight glasses a day, but that's really a myth," says Sonja Swenson, MD, primary care physician at Mariner Clinic. Needed water can come from beverages and foods with a high water content, such as soup, fruits and vegetables. But the best guideline? "I tell people to drink when they are thirsty," says Dr. Swenson.
How Water Helps Your Body
Water helps your body in a number of ways. It keeps your temperature normal, it lubricates and cushions joints, protects your spinal cord and other tissue, and removes waste. Your body loses water when it performs its normal functions, such as sweating or going to the bathroom. You need to replace this water, especially if you are doing a strenuous activity, if the weather is hot or if you are sick.
How Much Should You Drink?
In 2004 the Institute of Medicine issued recommendations for water intake. The report found that most people meet their daily needs for water, using thirst as a guide, just as Dr. Swenson recommends. The report defines recommended water intake for women at 2.7 liters per day (91 ounces, or 9 ten-ounce bottles), and for men, 3.7 liters per day (125 ounces, or 12-1/2 ten-ounce bottles).
How Do You Know When You're Drinking Enough Water?
The Boy Scouts of America also have an excellent resource about the heat index and hydration. While focused on warm weather, it also includes a urine color chart. The chart is an education tool that can help you stay aware of when you may be dehydrated and need to drink more water. If you are well-hydrated, your urine should be light, like the color of lemonade, unless you are taking a supplement or eating foods that impact the color. "If your urine is a bright yellow, or a darker color even if you are increasing your fluids, then you should get it checked, because it could mean there are problems with your kidneys or liver," says Dr. Swenson.
Choosing Healthy Options
Plain water is always best, but for those who want more variety, the Centers for Disease Control has a website called "Rethink Your Drink." It's designed to help people who want to lose weight, but the tips are also good for helping with hydration, such as drinking sparkling water with lemon instead of sugar-sweetened ice tea.