Is there a predetermined amount of water we should drink each day?
From a report published in August 8, 2002 by Heinz Valtin of the Department of Physiology, Dartmouth Medical School.
"Despite the seemingly ubiquitous admonition to "drink at least eight 8-oz glasses of water a day" (with an accompanying reminder that beverages containing caffeine and alcohol do not count), rigorous proof for this counsel appears to be lacking."
"In summary, this article is concerned with fluid intake for healthy adults in a temperate climate, performing, at most, mild exercise. Excluded were any special circumstances, such as illnesses, hot climates, and strenuous work or exercise."
"Finally, in view of the strong suggestive evidence cited above, I would argue further that for the time being the burden of proof that everyone needs 8 × 8 should fall on those who persist in advocating the high fluid intake without, apparently, citing any scientific support."
"In contrast to the need for final proof in support of 8 × 8, there is now strong scientific evidence that not all of the prescribed fluid need be in the form of water. Through careful experiments that passed peer review, Grandjean and colleagues have shown that caffeinated drinks (coffee, tea, and soft drinks) should indeed count toward the daily fluid intake in the vast majority of persons (40). And, to a lesser extent, the same may be true for mild alcoholic beverages
(79a, 84), such as beer consumed in moderation. Yet, the interdiction of these two types of beverages continues to be emphasized by proponents of 8 × 8 (3, 10, 17, 26, 42, 43, 59). Since for many adults caffeinated and alcoholic beverages constitute nearly one-half (Table 2) or slightly more (38) of the daily fluid intake, lifting these two restrictions raises the "effective" mean daily drinking fluid intake of adult Americans from the seemingly paltry amount of ~900 ml to the respectable one of 1,700 ml. And the last figure, of course, does not include the water we derive from solid foods and metabolism (Table 3; Refs. 29, 46). Some think that even 1,700 ml may be as much as 1 liter in excess of what sedentary American adults need to drink to maintain physiological homeostasis (38).
Thus I have found no scientific proof that we must "drink at least eight glasses of water a day," nor proof, it must be admitted, that drinking less does absolutely no harm. However, the published data available to date strongly suggest that, with the exception of some diseases and special circumstances, such as strenuous physical activity, long airplane flights, and climate, we probably are currently drinking enough and possibly even more than enough."
Read the entire review
From reading the review it appears common sense rules. If you are thirsty, drink, and liquids containing water count. Obviously if you are in a hot climate or involved in strenuous activities you will require more water. Again, listen to your body. I was in Central America years ago doing physical labor and we were told to drink water every 20 minutes. I took their advice.
Potable water is water of quality high enough to be consumed without risk of harm.
Think you can go to an isolated stream lake or other water source and be safe? Those days are long gone. Even in past years one had to be careful of animal fecal matter entering upstream. Here are some contaminates that you should be aware of.
From Wikipedia:
"Parameters for drinking water quality typically fall under two categories: chemical/physical and microbiological. Chemical/physical parameters include heavy metals, trace organic compounds, total suspended solids (TSS), and turbidity. Microbiological parameters include Coliform bacteria, E. coli, and specific pathogenic species of bacteria (such as cholera-causing Vibrio cholerae), viruses, and protozoan parasites.
Chemical parameters tend to pose more of a chronic health risk through buildup of heavy metals although some components like nitrates/nitrites and arsenic may have a more immediate impact. Physical parameters affect the aesthetics and taste of the drinking water and may complicate the removal of microbial pathogens.
Originally, fecal contamination was determined with the presence of coliform bacteria, a convenient marker for a class of harmful fecal pathogens. The presence of fecal coliforms (like E. Coli) serves as an indication of contamination by sewage. Additional contaminants include protozoan oocysts such as Cryptosporidium sp., Giardia lamblia, Legionella, and viruses (enteric).[5] Microbial pathogenic parameters are typically of greatest concern because of their immediate health risk."
So now you may thinking, so what, I never go camping and I buy bottled water.Perhaps you think your municipal water system is safe and flooding is not a concern. However, power outages and damage to power systems are a real possibility.
Boulder CO problems in April 2007
Detroit MI August 2003
Widespread Oklahoma problems December 2007
In case you have not been paying attention.
"Solar Cycles
March 6, 2006“The NCAR team predicts the next cycle will be 30-50% more intense than the current cycle.”“Cycle 24 is likely to reach its peak about 2012"
March 10, 2006“This week researchers announced that a storm is coming–the most intense solar maximum in fifty years.”Dikpati’s forecast puts Solar Max at 2012"....Read more
"From a NASA-funded study by the National Academy of Sciences dated January 21, 2009:
“January 21, 2009: Did you know a solar flare can make your toilet stop working?
That’s the surprising conclusion of a NASA-funded study by the National Academy of Sciences entitled Severe Space Weather Events—Understanding Societal and Economic Impacts. In the 132-page report, experts detailed what might happen to our modern, high-tech society in the event of a “super solar flare” followed by an extreme geomagnetic storm. They found that almost nothing is immune from space weather—not even the water in your bathroom.”
“The problem begins with the electric power grid. “Electric power is modern society’s cornerstone technology on which virtually all other infrastructures and services depend,” the report notes. Yet it is particularly vulnerable to bad space weather. Ground currents induced during geomagnetic storms can actually melt the copper windings of transformers at the heart of many power distribution systems. Sprawling power lines act like antennas, picking up the currents and spreading the problem over a wide area. The most famous geomagnetic power outage happened during a space storm in March 1989 when six million people in Quebec lost power for 9 hours:”"
"“According to the report, power grids may be more vulnerable than ever. The problem is interconnectedness. In recent years, utilities have joined grids together to allow long-distance transmission of low-cost power to areas of sudden demand. On a hot summer day in California, for instance, people in Los Angeles might be running their air conditioners on power routed from Oregon. It makes economic sense—but not necessarily geomagnetic sense. Interconnectedness makes the system susceptible to wide-ranging “cascade failures.”"
“To estimate the scale of such a failure, report co-author John Kappenmann of the Metatech Corporation looked at the great geomagnetic storm of May 1921, which produced ground currents as much as ten times stronger than the 1989 Quebec storm, and modeled its effect on the modern power grid. He found more than 350 transformers at risk of permanent damage
and 130 million people without power. The loss of electricity would ripple across the social infrastructure with “water distribution affected within several hours; perishable foods and medications lost in 12-24 hours; loss of heating/air conditioning, sewage disposal, phone service, fuel re-supply and so on.”"....Read more
Future articles will provide ways of obtaining potable water when safe tap water or bottled water is not available.
The information provided above is believed to be accurate. Each person is unique. Check with your doctor if you have any questions.
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