Do You Really Need 8 Glasses of Water

Do You Really Need 8 Glasses of Water


Everyone knows that you need eight glasses of water each day.  Right?  But who says it’s right?

While we all think this is the best thing to do for our health, there is no scientific basis for the recommendation (NOTE: there is also no evidence drinking that much water is bad for you either).

The 8×8 (eight eight-ounce glasses) recommendation seems to have its origin with nutritionist Dr. Fredrick Stare.  It was based on his observation that food needed a set amount of water to digest properly in his view.

In short, the recommendation was to help you get 2000 calories through your digestive system and had nothing to do with staying hydrated.

What is really strange is that somehow his original recommendation was six glasses per day, but 8×8 was a catchier phrase that just caught on.

What is amazing about this “health fact” is there is no study to back it up, but simply a casual opinion.

Dr. Stare’s opinion said coffee and beer counted toward the 8×8, but the “conventional wisdom” states with certainty that these sources don’t count.

And those who echo the wisdom that 8×8 is a scientific fact, often don’t think the water in food counts either.

There is another theory where the 8×8 advice came from.  In 1945 the federal government started coming out with the Recommended Daily Allowances (RDA).  The recommendation was 64 ounces a day.

Why did the food board recommend this amount?  No one knows.

Americans get about 20% of our water needs from the food we eat.  The other 80% comes from beverages, only 30% of which is water.

We really don’t need a schedule.  As long as we are not ignoring our thirst, we should be in good shape.

The human body is designed to signal us for the need to drink well before dehydration occurs.


It is certainly possible to go too far in search of hydration.

Too much water will dilute the electrolyte levels in the bloodstream.  Then salt, potassium, and magnesium levels drop and will initially start causing cramps in the muscles and then the ultimate muscle cramp, a heart attack.

Drinking excess water does not create any known advantage to most people.  Athletes, especially in hot and humid conditions, of course, need more water, but it doesn’t seem to help with issues such as kidney stones.

Thankfully we seem to have a reflex that prevents excessive water consumption.  If we are listening to our thirst, we maintain a proper fluid balance.

So, it’s perfectly fine not to obsess over the idea that you are under some obligation to get two liters of water in your system every day.

If you think you are getting dehydrated, then look in the toilet after you go pee.

If it’s pale yellow, you are perfectly ok.  If it’s darker than usual you probably need more fluid.

CLICK HERE to see what else your pee can tell you.

All fluid counts toward taking care of your thirst.  You can drink coffee and tea without worrying about dehydrating yourself too.

It is always interesting and important to look at our assumptions of what we think we should do to stay healthy and see if there is any science to back it up.