60-Second Science

The Mythical Daily Water Requirement

There's no evidence that humans actually need the oft-cited "eight-glasses-per-day" of water. Karen Hopkin reports.














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Podcast Transcript: Somewhere along the line you’ve probably heard that you should drink eight glasses of water a day. It’s supposed to make your skin supple, keep your organs flush and help you avoid overeating. Now doctors from the University of Pennsylvania say that’s hogwash. After exploring the health effects of hydration, they conclude that the purported benefits of drinking lots of water are not backed by any solid evidence—or liquid evidence, either. The physicians present their findings in the June issue of the Journal of the American Society of Nephrology.
 
Okay, humans can’t last more than a few days without water. But very little research has been done to assess just how much water a healthy individual needs. So the Pennsylvania docs scanned the literature. They discovered that drinking water does help the kidneys clear out salt and such. But those studies don’t suggest any sort of clinical benefit. There are no studies that show that chugging H2O will curb your appetite. Ditto for drinking water to enhance your skin tone. In fact, no studies indicate that people should drink eight glasses of water a day. Where that number came from no one seems to know. But in the end, it turns out to be all wet.

—Karen Hopkin

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  1. 1. SteveAmstel 02:13 PM 11/25/08

    There is significant evidence to indicate that western societies are chronically dehydrated from drinking teas, sodas, coffee, and sports drinks as water replacements. With a diet full of diuretics and little or no fresh clean water intake, people do show evidence of disease and illness. This is area is being studied and will become more well documented over the next year. Our group MSI World is performing a cohort study on hundreds of persons to find a relationship between the intake of clean fresh water to reduction in illness. Please also reference F Batmanghelidj M.D.s books on the topic Your not Sick Your Thirsty and others. Further please review Dr. Shinyas book the Enzyme Factor in which he recommends that patients drink at least 1 liter of water 30 minutes before meals, and the amazing results his diet has had for many sick patients. It amazes me that when the body is 75% water doctors and scientist are still saying water intake is unimportant. We need to get clear that many idiopathic diseases are related to acidity and dehydration.

    Steve B Amstel MSIWorld.org

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  2. 2. Kopasetik 08:35 AM 12/1/08

    I totally agree with Steve B Amstel! Just look at the people in underdeveloped countries without safe clean water and see what the lack of water does on the body! We now have to watch the acidity of the water we are drinking so we don't add to the problem. With most bottled water being acidic, we are not helping our body rid themselves of the toxins we take in through breathing or otherwise.

    I am currently teaching a unit on water, water purification and related issues to all of my 9th grade students. The information and data is staggering and life altering to say the least! I hope my students see the big picture here and go forth to do something about educating the rest of society and the world, unlike most of the doctors and scientists mentioned in the last post.

    And when you think about it, if we don't get a new blood type soon, society as a whole is doomed! Our bodies weren't designed to process the foods and beverages that people are in-taking today. The staggering number of cancer is evidence enough. Acidosis is the root of all this evil.

    Wendy Green, Technology Educator

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  3. 3. somenath 11:52 PM 10/23/09

    I do understand water is important since upto 75 % of human body constitutes water . There is a reqirement of clean , healthy , potable and possiby neutral ph water for out kindeys to funciton normally . The amount is questionable . Possibly it varies from county to county as we see wide variation in geographic climate . Moreover dietary prefernces and ethnic groups and body mass are to be conidered . I do belive water is a necessity . The amount per day off course is to be found out after scientific study .

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  4. 4. somenath 11:56 PM 10/23/09

    I do belive that intake of clean , potable water is important for humans since upto 75 percent of out body constitutes water . Moreover our kinndy functioning , metabolism and enzymatic reactions are water dependent. Any study on water and its effect on humans has to be long term to answer the above question. Water in question should be free from harmful chemicals and bacteria and viruses and carcinogens that we are automaically believing - it may not be the case always.

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