How much water should I drink?

You've probably heard that you should drink 8 glasses of water a day. That's actually pretty close to the truth, but it depends on who you are, where you live, and how much exercise you get each day.

According to the Mayo Clinic, water makes up about 60% of your body weight and every system in your body depends on it. If you don't drink enough water, you may feel tired and even dehydrated. That's because your body keeps losing water through breathing, sweating, and urination. You need to continue to drink fluids to replace the water your body needs.

You know you are drinking enough water if you are usually not thirsty and your urine is clear or light yellow.

These helpful tips from the Mayo Clinic will help you figure out how much water to drink each day:

• Most men need about 13 cups of fluid a day, and most women need about 9.
• While water is best, some drinks like milk and juice are mostly water, so those count as well. Beverages that contain caffeine, alcohol, or a lot of sugar, such as beer, wine, coffee, tea, and sodas, should be limited.
• Food also contains fluid. A typical diet provides about 20% (or 1/5) of the fluids you need. Many fruits and vegetables, such as watermelon and zucchini, are mostly water by weight.
• You need more fluids to replace what you lose through perspiration. Drink an extra cup or 2 of water after exercising, in hot or humid weather, or if you have a fever.
• You will probably also need more fluids in dry conditions such as indoors with the heat on, or at high altitudes.
•   Women who are pregnant need an extra cup of fluid a day, and women who are breastfeeding need about 4 extra cups.
• Bottom Line: Drink a glass of water with each meal, between each meal, and before, during, and after exercising.

some caveats

It is possible to drink too much water and overload the kidneys; however, this occurs only rarely and almost never in healthy adults eating a normal diet.

Some people with health conditions such as heart failure and some types of kidney, liver, and adrenal gland disease may be told by their doctor to limit the amount of fluid they drink.