Does any drink with no calories count as water?

Thanks for your question, Sarah B.!

The answer is "it depends who you ask". Some people believe your water intake must be pure water to count, because there are additives in other beverages that prevent you from being fully hydrated. Just today someone told me that the 'chemicals' in soda 'stay in your body and never leave'... not true, of course, but everyone has their own thoughts on this subject.

Recently I read an article in a medical journal that denounced the old theory that 'coffee doesn't count as water, because the caffeine contained in coffee acts as a diuretic". They have now apparently shown that the diuretic effect (which makes your kidneys eliminate more water) is not enough to counter the benefits of taking in the fluids while you're drinking the coffee.

So, yes, I believe that anything you drink counts as water--even beverages which contain calories, such as milk or juice-- because they put fluid in your system. Whether it's 8 cups of water versus 8 cups of soda definitely has an effect on your system in other ways, but as long as you drink plenty of 'fluids' you should remain well hydrated!

Why Eight Glasses of Water?

Wherever did the "Eight Glasses" of water requirement come from?

When working with patients to estimate their fluid needs, calculations are based on one's size and calorie intake. A person is estimated to need one cc (or one milliliter) of water for each calorie they consume. An average calorie intake is 2000 calories per day. This is the level on which the daily values are based on food labels. When translating the metric 2000 milliliters (ml) to ounces, you divide 2000 by 30 because there are 30 ml in one ounce. You get 66 ounces, divide by 8 ounces per cup, and that is just over eight cups of water! This is why you always hear people suggest you need about eight, 8-oz cups of water each day.

If you are a larger person and consume more calories or if you are more active, you will need to adjust upwards and drink a few more glasses to adjust for metabolizing the extra calories, or to compensate for losses in sweat. Likewise, if you are a smaller person and consume fewer calories you might be fine drinking just six glasses of fluid each day. Extra fluids you do drink in moderation are easily excreted by your kidneys, so unless your doctor has suggested otherwise, at least eight glasses is suitable for anyone in good health.