How Much Water Per Day? Exaggerated by the Media!

March 12, 2009

Have you been pressured to drink more water than feels natural? Are you constantly coming up short of the recommended 8-10 glasses of water per day? You will like this article! I’m going to examine current studies that question the logic of drinking 8-10+ glasses of water per day. Newer studies are showing that maybe you should follow your senses, instead of sticking to some rigid drinking schedule.
bottled water
[When you are thirsty, nothing sounds better than water. So what should you do if you are not thirsty?]

Does Drinking 8-10 Glasses of Water Each Day Feel Natural?

If drinking that much water per day feels natural then by all means, go ahead and drink that much. For me, this just makes my entire day feels focused around drinking water. This is the same feeling I got when I used to try and eat 6 meals per day…I just don’t want my day to be devoted to consuming food and water. Even worse than that is the increased trips to the restroom that accompany that type of water intake.

The Average Person Loses 10 Cups of Water Per Day

Wouldn’t that mean that the average person would need to drink 10 cups of water per day? Well…it isn’t that simple. The average person also gets 4 cups of water from food. For instance, a watermelon is 92% water by weight, an egg is about 75% water, a piece of lean meat is about 70% water. So that leaves just 6 cups of water, right? Well, not exactly…

Coffee, Tea and Other Caffeinated Beverages Count!

I have always felt that caffeinated beverages were hydrating, but for some reason the mainstream media claims that the diuretic effect of the caffeine offsets any fluid in the beverage. Here is an interesting study which shows that coffee, tea, milk, soda, and other fluids have the same effect as water as far as hydration is concerned:
The Effect of Caffeinated, Non-Caffeinated, Caloric and Non-Caloric Beverages on Hydration

Here is what Ann Grandjean, the study’s lead author had to say…”We found no significant differences at all. The purpose of the study was to find out if caffeine is dehydrating in healthy people who are drinking normal amounts of it. It is not.” The same goes for tea, juice, milk and caffeinated sodas: One glass provides about the same amount of hydrating fluid as a glass of water. The only common drinks that produce a net loss of fluids are those containing alcohol.

A Kidney Physiologist Who Recommends Much Less Water

From a Los Angeles Article titled “All That Water Advice Just Doesn’t Wash” – 15 January 2001:

Kidney specialists do agree on one thing, however: that the 8-by-8 rule is a gross overestimate of any required minimum. To replace daily losses of water, an average-sized adult with healthy kidneys sitting in a temperate climate needs no more than one liter of fluid, according to Jurgen Schnermann, a kidney physiologist at the National Institutes of Health.

One liter is the equivalent of about four 8-ounce glasses. According to most estimates, that’s roughly the amount of water most Americans get in solid food. In short, though doctors don’t recommend it, many of us could cover our bare-minimum daily water needs without drinking anything during the day.

What About This? “If You Are Thirsty, Then It is Too Late”

It is often stated that by the time a person is thirsty, then that person is already dehydrated. I have always had a feeling that our bodies are smarter than that. Luckily I have found some scientific studies which back this up. Here is a study showing that people who waited until they were thirsty to drink water, remained just as hydrated as people who drank on a set schedule. So maybe our natural thirst mechanism actually works properly! Body Fluid Changes, Thirst and Drinking in Man During Free Access to Water

How Much More Water Does An Active Person Need?

I guess this would be one of the big variables. Obviously an exceptionally active person would need a more water compared to a less active person. Also, warmer climates and different altitudes would make a difference in how much water someone needs to consume.

Your Body Will Tell You How Much Water You Need

Drink water when you are thirsty and drink a little more than that if you enjoy water, but don’t freak out if you aren’t hitting the 8-10 glasses per day figure. I drink a cup of coffee in the morning, tea during the day, a cup of coffee before I work out, and then 4-5 cups of water the hours after working out until bed time. This feels like more than enough water. Bottom line is this…drinking a glass of water every 2 hours certainly won’t harm you, but don’t worry if you can’t drink water on such a structure schedule.

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{ 24 comments… read them below or add one }

Michael - theFatLossAuthority March 14, 2009 at 7:32 pm

Nice article Rusty. As stated by others, I use my urine as an indicator for hydration. Been clear for a long time;)

Marc Feel Good Eating March 15, 2009 at 7:24 am

Great post Rusty!
I’m in COMPLETE agreement. As an intersting side note, look back to see WHEN this 8-10 a day advice came out. You will find that it correlates exactly to the time when bottled water really started making a presence. Starting in the early 90’s.


pnw fitness March 15, 2009 at 7:36 am


Probably some truth to tap water chemicals. Mines really not so bad, but on a recent trip to Arizona, I could swear I was drinking acid.

I’ll be on a well soon & I just bought a PUR filter. Pretty cheap, so I figured why not?

AlainaOfArc March 15, 2009 at 4:39 pm

Personally, for me, drinking about 64 oz. of water a day has made me feel great. I’ve stopped drinking any fruit juice, pop (I’m Canadian), fruit drink, etc. and have lost 5 pounds in the last month. I don’t have to pee all that much more than before, and I just feel so much clearer and cleaner. Sometimes I’ll drink a cup of white tea in there, but usually, I just stick to water (and yes, I drink the tap water, knowing full well what’s in it – I can’t afford to pay for any other type of water, but that’s a different story).

But the thing is, that’s ME. In my own path to improved health, drinking water has been one change that I found works. It’s not going to work for everyone (though I do think if the average person replaced even one glass of juice/drink a day with water, they would see improvements in their health).

We’re all different, and a blanket recommendation of 8 glasses a day isn’t going to work for everyone. But neither is saying that people get enough water from their food – it really depends on what people are eating. Lots of raw foods, then it’s possible. Highly processed, highly salted and packed with sugar? Not so likely.

Yash March 15, 2009 at 4:41 pm

Great post once again Rusty. I never bought into the 8 glasses a day thing. It seemed excessive. I think a few glasses on top of your daily food consumption doesnt hurt though. /especially considering other fitness goals that people may have. For fat/weight loss, drinking water and making sure to avoid even minimal dehydration can make the body less likely to store water weight. On the flip side, hydration is important for muscle building because more fluid helps the amino acids get to your msucles as well as siphon away some of the waste. This is basically what creatine does besides provide energy for workouts, it provides more water to your muscles. Bascially, you don’t need to go overboard, but considering we are largely comprised of water, some extra won’t hurt you.

Anthony March 16, 2009 at 1:24 am

i consciously think about getting my 8 during every day so i can relate to this post. while water is definitely healthy, as we can’t survive without it, this post was illuminating as i never considered whether or not we really not the 8, and sometimes i feel more full than i should feel. interestingly enough, water is usually all i ever drink apart from orange juice or cranberry juice.

Chris - March 16, 2009 at 9:58 am

Matthias said:

To all the “your body is smart” guys and girls: Why do people get fat?

A big part of this is that the Standard American Diet contains a ton of crap foods that our bodies are not well equipped to deal with. It is also worth considering that our body views gaining weight as a survival advantage, i.e. storing energy for the future. Most of the super dense foods that are staples today were not present during most of our evolution. The fat storage mechanisms work just fine for the circumstances they developed in.

Only eating actual food (naturally raised meat, fruit, vegetables, nuts) and only eating when you’re hungry will keep most, but not all people at a healthy weight.

brit lankan March 16, 2009 at 1:30 pm

i only found out this site three days ago, it’s ace!!, i started a bodybuilding routine when i was 15 and i gained a load of muscle but still kept the fat, ( i was chubby), im 17 now with a dramatic loss it body fat, but still having a hard time getting rid of all that cubb.

because i have to go to scool, and am exhausted all weekend, i have hard time dieting and sticking to a routine, what do u recommend

Mike OD - LifeSpotlight March 16, 2009 at 3:47 pm

Good stuff. I used to try and drink a gallon every day long ago…and spent my day in the bathroom for the most part. Now I go by how I feel….days higher in protein/fat I love the taste of water….other days higher in carbs and my body doesn’t ask for much….when I fast with IF I don’t seem to need much…..eating fruit (which is mostly water anyways) and that seems to take care of it too. Beats spending all day running to go pee every hour!

admin March 16, 2009 at 4:15 pm


Yeah, we can learn a decent amount from animals. I do try to dig deep into subjects instead of just trusting what is considered “common knowledge”. Sometimes it takes a long time for people to change their beliefs and it takes 10+ years after a study proves the opposite for people to change their way of thinking.


You bet. A lot of the times I can’t drink that much water either. Today I have a tough HIIT workout, so I did slam down about 32 ounces…but most days I drink much less. The main thing is that you don’t have to feel guilty about following your instincts.


I use the urine test as well. I never thought I would talk so much about urine! Funny stuff.


That does make sense that the bottled water companies would enjoy people to drink more water. I wonder if they funded any studies “proving” their point (like many supplement companies do).

pnm fitness,

Arizona has some nasty tasting tap water. Some pretty sick stuff in parts of California as well. I swear I have had water in California that gave me Montezuma’s Revenge. Not a knock on California…it is probably my favorite state in the US.


People certainly do need to adjust for their particular circumstances. There are quite a few people who would benefit from drinking a bit more water.


People taking creatine, would benefit from drinking a little bit more water each day, but like you said no reason to go overboard.


Water is great stuff. If you were to chose one liquid, it is the way to go. Juice is good stuff, but if you want to get extra lean for a vacation or some special event, you should consider dropping it from your diet for 6-8 weeks. I prefer the actual fruit, because the fiber in the fruit slows the absorption of the calories. This way you don’t get a blood sugar spike, rise in insulin, etc.


Good point. We have created a lot of calorie dense foods that don’t exist in nature. If we stuck to the foods provided by nature most of us would stay lean. Very well put.


School can tire you out, but I’m guessing that your diet may have something to do with that as well. Do you eat a big lunch or breakfast? If you do, I would suggest eating lighter for breakfast and lunch, workout after school, and eat a realistic, but generous portion of food for dinner. If you are lucky enough to have a mom that cooks for you, then eat her home cooking. This way you are getting more healthy home cooked food and less of that crap from the vending machines (which is what I ate in school…not good).


Fit J March 16, 2009 at 7:29 pm

I see your point dude, but it’s only un-natural if you are truly forcing yourself. Here’s my detailed take on it.

As for energy levels, I have MORE energy since I eat 6 WELL ROUNDED AND BALANCED meals. When I say meals I’m not referring to a 700calorie dinner, just something small thats about 400 calories.

Small meals are easier to digest, you’ll have more energy if you eat 6 meals that are 300 calories each, as opposed to 3 meals that are 600 calories each. I’ve tested this with myself and my clients over and over.

As for it feeling un-natural… I agree, it does. At first, but I’m at a point now where I train with some serious intensity and my active lifestyle just demands it, and now it feels un-natural NOT to eat frequently. Get what I’m saying?

Anyways, my 2cents. Keep up the blog.

Tyler March 16, 2009 at 9:20 pm

Hey rusty I’ve been reading your advice about how to get the Hollywood look I use to be 185 now I am 6 ft 165-170. I was wondering if that’s to skinny. Guys at the gym see me and say I’m so small even though I have the best abs I’ve ever had at this weight. I was wondering being at 6 ft what is a good weight to be at. What are some of the other celebs at my heights weight

Simple Health Exercises March 18, 2009 at 2:33 am

Hi Rusty just thinking what a great name when writing about WATER doh … water is the most hardest liquid to get the habit of … so heres my tip to make sure you follow what this message is all about here … my way to make sure I drink enough of this liquid gold the life’s blood of this planet!! … is to have 8 small bottles dotted around my home office and every time I pass one of these bottles I take a swig and roll around my mouth a few times before swallowing to give my body time to realize whats on its way to my stomach then it seems to rest better in my gut until I’m ready for my next swig … after a month of doing it this way you soon realize the benefits of drinking the right recommended quantities of this liquid gold …your body responds by making you feel so good

Regards and all my best to you and your water habits
Phillip skinner

admin March 21, 2009 at 2:50 pm

Fit J,

That makes sense. I know different people respond to different ways of eating. I’m more of a “bigger meal and eat less often” guy, but I know some people do better with frequent eating. Overall, as long as the calories are kept in check either approach can work.


Sounds like you have a build similar to Cam Gigandet in “Never Back Down”…lean with sharp abs. Don’t worry about how the guys respond, the ladies are going to dig that look!


That sounds like a great technique to getting enough water. I still would probably wind up drinking too much, since I have the habit of chugging liquids quickly…but it does sound like a decent solution.


Lori March 22, 2009 at 12:19 am

hello rusty…

yeah, i drink water all day… first thing when i wake, i crave it… but could we drink too much? i have drank well over a gallon at times, and i love it… i don’t feel i’m “trying” to drink, i just do…

also, i have heard that over weight people should drink more…

do you think this is true?

anyway… i love water… and enjoy it… in the morning, freezing cold, in the afternoon cool, at night cold…

i just love water… and feel i want it all the more if i drink coffee or especially soda…

ps… i am down 7 pounds, and walk/jogging 5 miles a day now!

thanks again for the great read!

Chris March 27, 2009 at 4:26 am

Did anybody else notice this in the acknowledgements of the hydration study? –

“Supported by a grant from The Coca-Cola Company.”

BMatt April 22, 2009 at 11:14 pm

haha…only when he’s thirsty…

My greyhound sometimes goes an entire day without drinking any water, and she’ll usually drink a couple cups after I sprint with her. Listening to one’s body is usually best.

Studio Element Personal Training May 27, 2009 at 10:42 pm

I always thought it was a bit exaggerated. Either way, I think most people do not get enough hydration in their daily life. I always encourage my clientele to drink more.

Alister Lane MD September 30, 2009 at 4:47 am

Good news!

Really informative Rusty – I’m especially happy to hear about coffee and other caffeinated beverages. It always seemed nonsensical to me that beverages consisting mainly of water were considered dehydrating. Nice to hear that the experts agree.

lallo badall January 12, 2010 at 10:39 am

drinking 8 glasses is too much strain on the kidneys, and on frequent nite bathroom trips.

I now drink about 4 ozs of water per day, just one trip to the bathroom.

Eric May 25, 2010 at 9:55 am

Don’t believe it. Being hungry is often confused with being thirsty. I’ve also seen stats that 75% of the people in the US are walking around dehydrated from insufficient water.

Its also an overgeneralization to say 8 glasses. I’ve seen recommendations of 1/2oz per lb bodyweight.

julius spisak February 21, 2011 at 3:45 pm

Hello! I have to drink 80-10 liters a day sweetened water. If not Drink the amount of whole body itches me. Can you tell me why?

Ahmed-LivingNotSurviving May 24, 2011 at 4:27 pm

I use to hear the thirsty/dehydration line all the time, and it NEVER made sense.

I completely agree Rusty, our bodies are way more efficient than most people think. Nice article.

Toni August 24, 2011 at 10:53 am

I have always thought drinking 8-10 glasses daily of just pure water sounded like so much work to me. I always fell short but now I do what you do, Rusty, maybe 5 glasses of water peppered in with some green tea and a cup of black coffee. That’s more than enough for me as well.

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