Do You Really Need Eight Glasses of Water a Day?

We can exist without food for months, but without water we can only survive a few days.  Your body is made up mostly of water, which is essential for digestion, nutrient absorption and elimination, aids circulation, helps control the body’s temperature, lubricates and cushions joints, keeps the skin healthy and helps remove toxins from your body.  Every day you lose water from your body through urine and sweat and the fluid needs to be replaced.

I have often told my patients they need to drink at least eight eight ounce glasses of pure water per day.  Then in April, 2004 I read a story in Family Practice News(http://www.familypracticenews.com/) that suggested letting thirst be your guide may be the way to go. (I am unable to find the article at this time.)
Despite concerns that caffeine and alcohol are diuretic, they can count towards daily fluid intake.  For women, 2.7 liters (91 ounces) and for men, 3.7 liters (125 ounces) per day is the recommended total from all beverages and foods each day.  If it is hot outside, you have a fever or you are exercising, you will require more water than normal and should drink more in these cases.
As a person grows older, they sometimes can’t tell that they are thirsty,  so older adults will want to be sure to drink water regularly.
Dr. Joseph Mercola (mercola.com) recommends using the color of your urine as a guide to how much water you should be drinking.  As long as you are not taking riboflavin (B2, which in most cases turns urine bright yellow), then your urine should be a very light yellow.  If it is a deep yellow, then you are not drinking enough water.  
I often look for chapped lips, tenting (where skin on the back of the hand returns more slowly to its original position), complaints of constipation, or if the person has an occupation of real estate agent.
What type of water should you be drinking?  The answer is clean, spring water and filtered water.  I don’t recommend drinking unfiltered water, distilled water or fluoridated water.  Make sure to read the report from your local tap water supplier that’s usually mailed to you yearly.  This will help you determine what type of filter you need to make sure your water is free from contaminates such as heavy metals and bacteria.  That said, tap water in the United States is generally quite safe to drink.  (http://water.epa.gov/drink/guide/upload/book_waterontap_full.pdf)
The reason why filtering your own water is important  is that bottled water is a huge strain on the environment.  Plus, some bottled water may not be any cleaner than tap water and the bottles water is in can leach unsafe chemicals called BPA into your water.

My conclusion is that if you feel thirsty, have something to drink.  If you are not thirsty, don’t drink unless you want to. If you are older, bigger than normal, a real estate agent, suffer from constipation, diarrhea or chapped lips you may want to set up reminders to drink more water on a regular basis. Remember there are fluids in the foods you eat so you may not need to drink eight glasses of water per day.
Do you keep track of how much water or fluids you drink?  How much do you drink?