Streams

The Right Amount of Water

Friday, September 13, 2013

The First Lady is encouraging Americans to drink water as part of her Drink Up campaign, but some in the medical community are pushing back against the idea of uniform hydration advice. Douglas J. Casa, chief operating officer of The Korey Stringer Institute, and a professor of kinesiology at the Neag School of Education at University of Connecticut, explains what is known about how much water is the right amount to drink and what listeners can do to stay hydrated.

Guests:

Douglas Casa
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Comments [20]

Danielet from Bklyn

You have a complex endocrine system to dilute your body and another to concentrate. Both work through the kidney. But the brain takes a long time to hydrate and even longer to dehydrate....and that's where excess water (edema) or dehydration are most dangerous. Your brain can over-ride your body's equilibration systems in a desperate effort to equilibrate. But as slow as isthe body's fluid equilibration, the brain's is a lot slower. So it is best to drink SLOWLY and REGULARLY throughout the day, giving the opposing hormone systems time to equilibrate without affecting your brain's liquidity. ABOVE ALL, do not engage in physical activity with a full bladder, that's deadly if you take a blow to the lower abdomen. Take time to keep drinking-- ALL DAY-- a couple of gulps and to urinate regularly. Your body will do the rest and it won't be as fooled by the color of your urine as will your mind. Just remember that equilibration TAKES TIME and going too long without drinking at regular intervals a couple of gulps each time or binging on water or, worst still, on lots of soda (that could really damage your kidneys) the hormonal equilibration systems will be too slow to avoid organ damage, no matter how small it seems when you are young. Worst of all, engaging in too much intake or too little intake for too long, you will do sever damage to your brain that will take too long to recover because the BLOOD BRAIN BARRIER makes water flow in both directions much too slow for you to recover from brain edema or brain shrinking. Since the brain is extremely vulnerable to any change is sodium solution on its side of the blood brain barrier, it cannot recover as well as your kidneys, heart and muscles. And what damage you do to your brain is forever!

So keep drinking a couple of gulps every ten minutes or so REGULARLY (increasing when it's hot or you are sweating) and start the day with a pint of fluid for breakfast because the body dehydrates a lot in your sleep. NEVER FORGET, the brain takes a long time to suffer from hyper/hypo hydration and once the damage is done it is forever. BRAIN SWELLING or SHRINKING can kill!!!

Sep. 27 2013 02:24 PM
domnuledoctor from Bklyn

You are not a passive glass. You have a hormone system for concentration urine and one for diluting. These systems,if they work well, will salvage water or get rid of it. Hypo- hyper dilution or electrolytes levels are maintained. The issue is how fast or how slow you take in water. So, drinking a pint of water can be toxic or beneficial DEPENDING ON HOW *FAST* you do it. There is a rate of equilibration that these hormones regulate that is a lot slower than you can drink. Furthermore, you can go without drinking or feeling thirst even while your kidney is being damaged and your tissues suffer toxemia from wastes not cleaned out by water in blood. So the issue is to keep water intake GRADUAL and CONSTANT. DO NOT GO BY URINE COLOR as it by thirst. Keep water intake and output so that the time between urinations is constant and the water intake is too. Just recall that you can swallow water a lot faster than you can get it into the blood so consistent drinking SLOWLY increasing in amount, NOT RATE, when you perspire will keep you well hydrated. Above all, remember not to break consistency of water intake with long breaks and long binges because you body can adjust only slowly so dehydration takes at least two hours to fully equilibrate. By then you may add insult to injury by binging. Don't drink more when you eat salt because GRADUALLY your body will balance both but for a significant period your body will suffer from too much of both. Lastly, hypo/hyper hydration first affects your body and only later your brain. Thus, dehydration of the brain takes a long time to reverse. So just keep the water coming gradually and don't play sports with a full bladder; that's dangerous!

Sep. 27 2013 01:39 PM
Edward from Washington Heights AKA pretentious Hudson Heights

A glass of COLD NYC water is THE BEST drink in the world.

Sep. 13 2013 12:23 PM
Truth & Beauty from Brooklyn

Answers to some questions below:

1. Caffeinated beverages - coffee, tea, soft drinks - are not adequate to hydrate or rehydrate because caffeine is a dieuretic (makes you pee). Only decaf versions are counted as fluids.

2. How much you drink is also affected by what you eat. The body extracts water from food you digest, but some foods are denser than others, so you'd need to drink more after a serving of steak than you would after a serving of watermelon.

3. Sugar-free or diet soft drinks are very bad for you. According to the news and latest health reports, trying to trick your body by substituting fake sweetness for sugar doesn't work and most people who depend on sugar-free soft drinks tend to gain weight rather than lose because the body will seek sugar in other food sources.

4. Seltzer is merely water (H2O) with carbon dioxide (CO2) added for fizz; flavored seltzers are best for water replacement if you just can't stand plain water. Many brands add preservatives and artificial sweeteners, which are not necessary. Plain, naturally flavored seltzer is equivalent to water in all ways. No fat, no calories, no artificial ingredients.

Basically, if you want to lose weight, try to substitute a 12 oz, 0 calorie glass of water for a 12 oz, 160 calorie soft drink every day.

Sep. 13 2013 12:17 PM
emjayay from Brooklyn

To answer the coffee and tea questions, there has been recent research on this after a long time of people just saying they're bad because of the diuretic effect. Actually there is a bit of diuretic effect of caffeinated drinks, but it isn't huge. In actual research situation caffienated drinks hydrated almost as well as an equivalent amount of water. And diet soda probably isn't a problem either. It's all mainly water and it will all hydrate about the same. The sugars/caloric content of nondiet soda is the problem.

No one can say how much water anyone needs to drink because the individual need varies so much. In hot temperatures or if you heat yourself up with exercise you sweat way more water than you think. If it's hot and low humidity you lose litre after litre without having any way of knowing it. If you are on a plane for many hours you are in a low humidity situation which may be different from what you are used to and don't have water handy stuck in your seat and may get dehydrated without realising it. Like the guest said if you have diarhea you lose a lot of water.

The urine color thing the guest talked about is the only way to know about whether you are doing OK with hydration, other than just paying attention to what your body tells you. Your dog doesn't have to check their urine to know whether to hit the water bowl.

Sep. 13 2013 12:10 PM
Mike from Tribeca

Michael D. D. White from Brooklyn Heights -- Regarding "Lawrence of Arabia," drinking lots of water is how David stayed Lean.

Sep. 13 2013 12:06 PM
jgarbuz from Queens

I think Dr. Atkins somewhere wrote that our desire for sugar is really a desire for water, and that we should drink water to quench that desire for something sweet. I drink water all day, and try to drink away my desire for sweets.I'm definitely not fat, though I have the propensity to be if I did not control myself and follow Atkin's advice.

Sep. 13 2013 12:00 PM
Michael D. D. White from Brooklyn Heights

Any comment on the scene in "Lawrence of Arabia" when Lawrence declines the opportunity to drink from his canteen?

Sep. 13 2013 12:00 PM

Urge to Urinate would be a great punk rock band name

Sep. 13 2013 11:58 AM

@DS...go about your business citizen

Sep. 13 2013 11:58 AM
Bill from Danbury

If drinking when thirsty indicates mild dehydration, does that mean animals are dehydrated

Sep. 13 2013 11:57 AM
DS from New Jersey

Doctor has recommended sports drinks when research proves there is no value to these over water. Is it a coincidence that his institute is funded by Gatorade?

Sep. 13 2013 11:55 AM
robert from brooklyn

What about tea? Many cultures drink tea because the water supply is questionable and has to be boiled anyways. Is tea adequate for rehydration?

Sep. 13 2013 11:53 AM
JZ from Windsor Terrace

How does coffee affect hydration?

Sep. 13 2013 11:51 AM
Truth & Beauty from Brooklyn

I think your guest is correct in what the correct amount of water each person should drink is. I also believe that it is possible to drink TOO MUCH water, as it flushes out all the water soluble vitamins in the body and can cause problems with the brain.

HOWEVER, I think Mrs. Obama's focus is probably more on replacing sugary drinks with water. If each child would replace just one soft drink with an equal amount of water each day, that alone would be better for the body.

Sep. 13 2013 11:51 AM
Larrylarr from NYC

BRIAN...he didn't and you didn't let him finish the answer re: How many glasses a day are required?

Sep. 13 2013 11:50 AM
BK from Hoboken

I think the issue is less how much water to drink and should be more about drinking water in lieu of soda, juice, etc. I have read that kids today get one third of their caloric intake via what they drink. That's gross.

Sep. 13 2013 11:50 AM
Amy from Manhattan

They're not underquenched, they're overquenched w/overly sugary & often chemically enhanced liquids other than water. Did you know most so-called smart & vitamin waters are loaded w/sugar?

Also, I hope Prof. Casa refills his water bottle instead of buying more bottled water!

Sep. 13 2013 11:49 AM

So a person cannot determine how much water he/she should drink. We need an expert....man this is silly

Sep. 13 2013 11:48 AM
Mike from Tribeca

I've read that the prevalence of kidney stones in children has risen sharply over the past several years, in the main because they (and their parents) would much rather drink sugary flavored drinks and sodas than plain old boring water.

I salute the first lady for shining a spotlight on this important health issue, which is rarely reported on by the corporate-owned advertisement-driven media.

Sep. 13 2013 11:39 AM

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