THE BIGGEST NUTRITIONAL MYTH TO DATE
“Everyone should drink eight, 8 oz. glasses of water a day.” This has become known as the 8/8 Rule.
We all experience a certain amount of water loss each day and this loss does need to be replaced. Some years ago, it was calculated that the average person, under normal circumstances, loses about 2 liters of water each day through urination, perspiration, and respiration (water vapor lost from the lungs with breathing). Someone (unknown) proposed that to remain hydrated, this meant that we needed to consume 64 ounces of water daily (8,8 oz. glasses). Surveys of typical populations of people suggested most people fell well short of drinking this amount of water each day so it was suggested that most people exist in a state of chronic dehydration. There is absolutely no clinical evidence that this is true and if true, no scientific studies have proven that mild chronic dehydration is unhealthy. The 8/8 rule did not take into consideration that most typical diets obtain significant amounts of water from other sources: beverages (coffee, tea, juices, ice, soups, etc.); most foods are 40-90 % water by weight and also contribute significant amounts of water; water is contributed as a by- product of cellular metabolism. Estimates are that water from these sources quantitates to about 2 liters a day. One could legitimately define this situation as “balanced” without the addition of extra water.
We humans, and all other animals, are pretty good at regulating our individual water intake. When we need to replace fluid, there is this highly accurate mechanism called thirst that prompts us to drink and one of the best drinks to have is water. We have been drinking fluids in response to thirst for all of human history and we would not likely survived as a human race if we had to constantly think about drinking water. All the 8/8 rule would have done is cause our kidneys to excrete large amounts of very dilute urine.
The thirst sensation is so efficient at telling us when and how much to drink, there are no concrete guidelines that dictate a definitive amount of water that an individual should drink. The amount depends on how physically active we are, the environmental temperature, how much water is contained in the food that we eat, and if we have any medical conditions.
Water is a critical nutrient for the cells of our body to function normally, but that doesn’t mean we need to “obsess over excess”. Just like our gasoline automobiles must have gas for the engine to run, the engine functions whether we have one gallon in the tank or twenty gallons. Conveniently, there is a gas gage, comparable to our thirst sensation, that tells us when we are getting low on fuel and need to “hydrate” the engine.
Following the 8/8 rule is claimed by many nutritionist, dieticians, and some physicians, to improve skin tone, assist with weight loss, reduce headaches and fatigue, improve concentration, lubricate joints, and eliminate constipation. However, there is no definitive research or clinical studies that provide evidence supporting these claims.
The kidneys are outstanding organs that remove waste and toxins from our bodies. Consuming excessive water does nothing to improve their detoxifying ability. As a matter of fact, if excessive water is consumed, the kidneys must work hard to eliminate the excess. Conversely, if we are volume depleted, the kidneys preserve water by concentrating the urine.
Manufacturers of bottled water push the message that more water is better and their businesses are making billions of dollars on the 8/8 myth in addition to fear- mongering about unproven health risk from claimed chronic dehydration.
Finally, there is risk to drinking too much water. Excess water dilutes sodium in the blood causing a condition known as hyponatremia or water intoxication. The symptoms are muscular cramps, headaches, mental confusion and if severe enough, generalized seizures and death. The excess water results in swelling of the body’s cells, particularly in the brain.
So, it is hopeful that the information presented here will convince folks to stop carrying around those little plastic water bottles and constantly sipping on them. If you believe, as I do, that the 8/8 rule is all a myth, this practice will seem to be even more annoying.
Dr. Tippett is the founder of CQHP, a concierge internal medicine practice, located at 1210 Commerce Dr. Suite 106 Greensboro, Ga. 30642. He can be reached at 706-510-59. Visit his website at www.drtippett.com