Human Body Hydration ; FLUID BALANCE

Fluid balance is an aspect of the homeostasis of living organisms in which the amount of water in the organism needs to be controlled, via osmoregulation and behavior, such that the concentrations of electrolytes (salts in solution) in the various body fluids are kept within healthy ranges. The core principle of fluid balance is that the amount of water lost from the body must equal the amount of water taken in; for example, in human homeostasis, the output (via respiration, perspiration, urination, defecation, and expectoration) must equal the input (via eating, drinking, and parenteral intake).

Euvolemia is the state of normal body fluid volume, including blood volume, interstitial fluid volume, and intracellular fluid volume; hypovolemia and hypervolemia are imbalances. Water is necessary for all life on Earth. Humans can survive for 4 to 6 weeks without food but only for a few days without water.
Profuse sweating can increase the need for electrolyte replacement. Water-electrolyte imbalance produces headache and fatigue if mild; illness if moderate, and sometimes even death if severe. For example, water intoxication (which results in hyponatremia), the process of consuming too much water too quickly, can be fatal. Deficits to body water result in volume contraction and dehydration. Diarrhea is a threat to both body water volume and electrolyte levels, which is why diseases that cause diarrhea are great threats to fluid balance.

Water consumption

The amount of water varies with the individual, as it depends on the condition of the subject, the amount of physical exercise, and on the environmental temperature and humidity. In the US, the reference daily intake (RDI) for water is 3.7 litres per day (l/day) for human males older than 18, and 2.7 l/day for human females older than 18 including water contained in food, beverages, and drinking water. The common misconception that everyone should drink two liters (68 ounces, or about eight 8-oz glasses) of water per day is not supported by scientific research. Various reviews of all the scientific literature on the topic performed in 2002 and 2008 could not find any solid scientific evidence that recommended drinking eight glasses of water per day. For example, people in hotter climates will require greater water intake than those in cooler climates. An individual's thirst provides a better guide for how much water they require rather than a specific, fixed number. A more flexible guideline is that a normal person should urinate 4 times per day, and the urine should be a light yellow color.

A constant supply is needed to replenish the fluids lost through normal physiological activities, such as respiration, perspiration and urination. Food contributes 0.5 to 1 l/day, and the metabolism of protein, fat, and carbohydrates produces another 0.25 to 0.4 l/day, which means that 2 to 3 l/day of water for men and 1 to 2 l/day of water for women should be consumed as fluid to meet the Recommended Daily Intake (RDI). you can follow the watercure protocol formula . Details available for free from this blogsite.

Trace elements

In terms of mineral nutrients intake, it is unclear what the drinking water contribution is. However, inorganic minerals generally enter surface water and ground water via storm water runoff or through the Earth's crust. Treatment processes also lead to the presence of some minerals. Examples include calcium, zinc, manganese, phosphate, fluoride and sodium compounds. Water generated from the biochemical metabolism of nutrients provides a significant proportion of the daily water requirements for some arthropods and desert animals, but provides only a small fraction of a human's necessary intake.

There are a variety of trace elements present in virtually all potable water, some of which play a role in metabolism. For example, sodium, potassium and chloride are common chemicals found in small amounts in most waters, and these elements play a role in body metabolism. Other elements such as fluoride, while arguably beneficial in low concentrations, can cause dental problems and other issues when present at high levels. Water is essential for the growth and maintenance of our bodies, as it is involved in a number of biological processes.

Medical use

Effects of illness

When a person is ill, fluid may also be lost through vomiting, diarrhea, and hemorrhage. An individual is at an increased risk of dehydration in these instances, as the kidneys will find it more difficult to match fluid loss by reducing urine output (the kidneys must produce at least some urine in order to excrete metabolic waste.)

Oral rehydration therapy

Main article: Oral rehydration therapy

 

Oral rehydration therapy (ORT), is type of fluid replacement used as a treatment for dehydration. In an acute hospital setting, fluid balance is monitored carefully. This provides information on the patient's state of hydration, renal function and cardiovascular function.

• If fluid loss is greater than fluid gain (for example if the patient vomits and has diarrhea), the patient is said to be in negative fluid balance. In this case, fluid is often given intravenously to compensate for the loss.
• On the other hand, a positive fluid balance (where fluid gain is greater than fluid loss) might suggest a problem with either the renal or cardiovascular system.

If blood pressure is low (hypotension), the filtration rate in the kidneys will lessen, causing less fluid reabsorption and thus less urine output.

An accurate measure of fluid balance is therefore an important diagnostic tool, and allows for prompt intervention to correct the imbalance.

Routes of fluid loss and gain

Fluid can leave the body in many ways. Fluid can enter the body as preformed water, ingested food and drink and to a lesser extent as metabolic water which is produced as a by-product of aerobic respiration (cellular respiration) and dehydration synthesis.

Input

A constant supply is needed to replenish the fluids lost through normal physiological activities, such as respiration, sweating and urination. Water generated from the biochemical metabolism of nutrients provides a significant proportion of the daily water requirements for some arthropods and desert animals, but provides only a small fraction of a human's necessary intake.
In the normal resting state, input of water through ingested fluids is approximately 1200 ml/day, from ingested foods 1000 ml/day and from aerobic respiration 300 ml/day, totaling 2500 ml/day.

Regulation of input

Main article: Thirst

Input of water is regulated mainly through ingested fluids, which, in turn, depends on thirst. An insufficiency of water results in an increased osmolarity in the extracellular fluid. This is sensed by osmoreceptors in the organum vasculosum of the lamina terminalis, which trigger thirst. Thirst can to some degree be voluntarily resisted, as during fluid restriction.

The human kidneys will normally adjust to varying levels of water intake. The kidneys will require time to adjust to the new water intake level. This can cause someone who drinks a lot of water to become dehydrated more easily than someone who routinely drinks less.

Output

• The majority of fluid output occurs via the urine, approximately 1500 ml/day (approx 1.59 qt/day) in the normal adult resting state.
• Some fluid is lost through perspiration (part of the body's temperature control mechanism) and as water vapor in expired air. These are termed "insensible fluid losses" as they cannot be easily measured. Some sources say insensible losses account for 500 to 650 ml/day (0.5 to 0.6 qt.) of water in adults, while other sources put the minimum value at 800 ml (0.8 qt.). In children, one calculation used for insensible fluid loss is 400 ml/m² body surface area.
• In addition, an adult loses approximately 100 ml/day of fluid through feces.
• For females, an additional 50 ml/day is lost through vaginal secretions.

These outputs are in balance with the input of ~2500 ml/day.

Regulation of output

The body's homeostatic control mechanisms, which maintain a constant internal environment, ensure that a balance between fluid gain and fluid loss is maintained. The hormones ADH (Anti-diuretic Hormone, also known as vasopressin) and Aldosterone play a major role in this.

• If the body is becoming fluid-deficient, there will be an increase in the secretion of these hormones, causing fluid to be retained by the kidneys and urine output to be reduced.
• Conversely, if fluid levels are excessive, secretion of these hormones is suppressed, resulting in less retention of fluid by the kidneys and a subsequent increase in the volume of urine produced.

Antidiuretic hormone

Main article: Antidiuretic hormone

If the body is becoming fluid-deficient, this will be sensed by osmoreceptors in the organum vasculosum of lamina terminalis and subfornical organ.These areas project to the supraoptic nucleus and paraventricular nucleus, which contain neurons that secrete the antidiuretic hormone, vasopressin, from their nerve endings in the posterior pituitary. Thus, there will be an increase in the secretion of antidiuretic hormone, causing fluid to be retained by the kidneys and urine output to be reduced.

Aldosterone

Main article: Renin-angiotensin system

 

A fluid-insufficiency causes a decreased perfusion of the juxtaglomerular apparatus in the kidneys. This activates the renin-angiotensin system. Among other actions, it causes renal tubules (i.e. the distal convoluted tubules and the cortical collecting ducts) to reabsorb more sodium and water from the urine. Potassium is secreted into the tubule in exchange for the sodium, which is reabsorbed. The activated renin-angiotensin system stimulates zona glomerulosa of the adrenal cortex which in turn secretes hormone aldosterone. This hormone stimulates the reabsorption of sodium ions from distal tubules and collecting ducts. Water in the tubular lumen cannot follow the sodium reabsorption osmotically, as this part of the kidney is impermeable to water; release of ADH (vasopressin) is required to increase expression of aquaporin channels in the cortical collecting duct, allowing reabsorption of water.

elderly still do not recognize they are thirsty

The tragedy of waiting to get thirsty hits home when it is realized that the sharpness of thirst perception is gradually lost, as we get older. Phillips and associates have shown that after 24 hours of water deprivation, the elderly still do not recognize they are thirsty: “The important finding is that despite their obvious physiologic need, the elderly subjects were not markedly thirsty.” Bruce and associates have shown that, between the ages of 20 to 70, the ratio of water inside the cells to the amount of water outside the cells drastically changes from 1.1 to 0.84. Undoubtedly this marked change in the intracellular water balance would not take place if the osmotic push and pull of life could favor water diffusion through the cell membranes everywhere in the body—at the rate of 0.001 centimeters per second. Only by relying on the reverse osmotic process of expanding the extracellular water content of the body, so as to filter and inject “load-free” water into vital cells by the actions of vasopressin and the renin-angiotensin-aldosterone systems—when the body physiology is constantly forced to rely on its drought- management programs—could such a drastic change in the water balance of the body result.

Waiting To Get Thirsty Is To Die Prematurely And Very Painfully.

Heinz Valtin, M.D. an emeritus professor at Dartmouth Medical School, has ventured the opinion that there is no scientific merit in drinking 8 x 8-ounce glasses of water a day and not waiting to get thirsty before correcting dehydration. This view, published in the American Journal of Physiology, August 2002, is the very foundation of all that is wrong with modern medicine, which is costing this nation $1.7 trillion a year, rising at the rate of 12 percent every year. Dr. Valtin’s view is as absurd as waiting for the final stages of a killer infection before giving the patient the appropriate antibiotics. His views are based on the erroneous assumption that dry mouth is an accurate sign of dehydration.

Like the colleagues he says he has consulted, Dr. Valtin does not seem to be aware of an important paradigm shift in medicine. All past views in medicine were based on the wrong assumption that it is the solutes in the body that regulate all functions and that the solvent has no direct role in any of the body’s physiological functions. In medical schools it is taught that water is only a solvent, a packing material and a means of transport, that water has no metabolic function of its own. I have come across this level of ignorance about the primary physiological role of water at another Ivy League medical school from another eminent professor of physiology who, like Dr. Valtin, researched and taught the water-regulatory mechanisms of the kidney to medical students and doctors. Only when I asked him what “hydrolysis” is, did the penny drop and he admitted the scientific fact that water is a nutrient and does indeed possess a dominant metabolic role in all physiological functions of the body.

Dr. Valtin’s emphasis on the water-regulatory role of the kidneys limits his knowledge to the body’s mechanisms of “deficit management” of the water needs of the body. He seems to base his views of thirst management of the body on the vital roles of vasopressin, the antidiuretic hormone, and the renin-angiotensin system, the elements that get engaged in the drought-management programs of the body, when the body has already become dehydrated. Indeed, he thinks dehydration is a state of the body when it loses 5 percent of its water content; and that one should wait until at some level of such water loss the urge to drink some kind of “fluid” will correct the water deficit in the body. This view might have seemed plausible 25 years ago. Today, it exposes the tragic limitations of knowledge of the human physiology that is available to a prestigious medical school in America.

In his recently published and widely reported assertions, Dr. Valtin does not take into consideration the fact that water is a nutrient. Its vital “hydrolytic” role would be lost to all the physiological functions that would be affected by its shortage in its osmotically “free state.” Another oversight is the fact that it is the interior of the cells of the body that would become drastically dehydrated. In dehydration, 66 percent of the water loss is from the interior of the cells, 26 percent of the loss is from extracellular fluid volume and only 8 percent of the loss is borne by the blood tissue in the vascular system, which constricts within its network of capillaries and maintains the integrity of the circulation system.

Philippa M, Wiggin has shown that the mechanism that controls or brings about the effective function of the cation pumps utilizes the energy transforming property of water, the solvent; “The source of energy for cation transport or ATP synthesis lies in increases in chemical potentials with increasing hydration of small cations and polyphosphate anions in the highly structured interfacial aqueous phase of the two phosphorylated intermediates.” Waiting to get thirsty, when the body fluids become concentrated before thirst is induced, one loses the energy-generating properties of water in the dehydrated cells of the body. This is a major reason why we should prevent dehydration, rather than wait to correct it. This new understanding of the role of water in cation exchange is enough justification to let the body engage in prudent surplus water management rather than forcing it into drought and deficit water management, which is what Dr. Valtin is recommending people to do.

In his research on the “conformational change in biological macromolecules,” Ephraim Katchalski-Katzir of the Weizmann Institute of Science has shown that the “proteins and enzymes of the body function more efficiently in solutions of lower viscosity.” Thus, water loss from the interior of the cells would adversely affect their efficiency of function. This finding alone negates Dr. Valtin’s view that we should let dehydration get established before drinking water. Since it is desirable that all cells of the body should function efficiently within their physiological roles, it would be more prudent to optimally hydrate the body rather than wait for the drought management programs of the body to induce thirst. Furthermore, it is much easier for the body to deal with a slight surplus of water than to suffer from its shortfall and have to ration and allocate water to vital organs at the expense of less vital functions of the body. The outcome of constantly circulating concentrated blood in the vascular system is truly an invitation to catastrophe.

The tragedy of waiting to get thirsty hits home when it is realized that the sharpness of thirst perception is gradually lost, as we get older. Phillips and associates have shown that after 24 hours of water deprivation, the elderly still do not recognize they are thirsty: “The important finding is that despite their obvious physiologic need, the elderly subjects were not markedly thirsty.” Bruce and associates have shown that, between the ages of 20 to 70, the ratio of water inside the cells to the amount of water outside the cells drastically changes from 1.1 to 0.84. Undoubtedly this marked change in the intracellular water balance would not take place if the osmotic push and pull of life could favor water diffusion through the cell membranes everywhere in the body—at the rate of 0.001 centimeters per second. Only by relying on the reverse osmotic process of expanding the extracellular water content of the body, so as to filter and inject “load-free” water into vital cells by the actions of vasopressin and the renin-angiotensin-aldosterone systems—when the body physiology is constantly forced to rely on its drought- management programs—could such a drastic change in the water balance of the body result.

Two other scientific discoveries are disregarded when Dr. Valtin recommends people should wait until they get thirsty before they drink water. One, the initiation of the thirst mechanisms is not triggered by vasopressin and the renin-angiotensin systems—these systems are only involved in water conservation and forced hydration of the cells. Thirst is initiated when the Na+-K+-ATPase pump is inadequately hydrated. It is water that generates voltage gradient by adequately hydrating the pump proteins in the neurotransmission systems of the body. This is the reason the brain tissue is 85 percent water and cannot endure the level of “thirst-inducing” dehydration that is considered safe in the article published by Dr. Valtin.

Two, the missing piece of the scientific puzzle in the water- regulatory mechanisms of the body, which has been exposed since 1987, and Dr. Valtin and his colleagues need to know about it, is the coupled activity of the neurotransmitter histamine to the efficiency of the cation exchange; its role in the initiation of the drought- management programs; and its role in the catabolic processes when the body is becoming more and more dehydrated. Based on the primary water-regulatory functions of histamine, and the active role of water in all physiologic and metabolic functions of the body—as the hydrolytic initiator of all solute functions—the symptoms of thirst are those produced by excess histamine activity and its subordinate mechanisms which get engaged in the drought- management programs of the body. They include asthma, allergies and the major pains of the body, such as heartburn, colitis pain, rheumatoid joint pain, back pain, migraine headaches, fibromyalgic pains, and even anginal pain. And, since vasopressin and the rennin-angiotensin-aldosterone activity in the body are subordinates to the activation of histamine, their role in raising the blood pressure is a part of the drought-management programs of the body. Their purpose of forced delivery of water into vital cells demands a greater injection pressure to counteract the direction of osmotic pull of water from inside the cells of the body, when it is dehydrated.

From the new perspective of my 22 years of clinical and scientific research into molecular physiology of dehydration, and the peer-reviewed introduction of a paradigm shift in medical science, recognizing histamine as a neurotransmitter in charge of the water regulation of the body, I can safely say the 60 million Americans with hypertension, the 110 million with chronic pains, the 15 million with diabetes, the 17 million with asthma, the 50 millions with allergies, and more, all did exactly as Dr. Valtin recommends. They all waited to get thirsty. Had they realized water is a natural antihistamine and a more effective diuretic, these people would have been saved the agony of their health problems.

References:

1. Wiggins PM; A Mechanism of ATP-Driven Cation Pumps; PP-266-269, Biophysics of Water, Eds. Felix Franks and Sheila F. Mathis, John Wiley and Sons, Ltd.1982
2. Ephraim Katchalski-Katzir: Conformational Changes In Biological Macromolecules; Biorheology, 21, PP. 57-74, 1984.
3. Phillips PA; Rolls BJ; Ledingham JGG; Forsling ML; Morton JJ; Crowe MJ and Wollner L; Reduced Thirst After Water Deprivation In Healthy Elderly Men; The New England Journal of Medicine, PP.753-759, Vol. 311, No. 12, Sept. 20 1985.
4. Bruce A; Anderson M; Arvidsson B and Isacksson B; Body Composition, Predictions of Normal body Potassium, Body Water and Body Fat in Adults on the Basis of Body Height, Body Weight and Age; Scand. J. Clin. Lab. Invest, 40, 461-473, 1980.
5. Batmanghelidj F. M.D. Pain: A Need For Paradigm Change; Anticancer Research, Vol. 7, No. 5 B, PP. 971-990, Sept.- Oct. 1987; full article posted on www.watercure.com
6. Batmanghelidj F. M.D. Your Body’s Many Cries for Water; Global Health Solutions, Inc.
7. Batmanghelidj F. M.D. Neurotransmitter Histamine: An Alternative View; Page 37 of the Book of Abstracts; The 3rd Interscience World Conference on Inflammation, Analgesics and Immunomodulators, 1989 Monte-Carlo. The Abstract and the full article are posted on the Website www.watercure.com
8. Batmanghelidj F. M.D; ABC of Asthma, Allergies and Lupus; Global Health Solutions, Inc.

For more information on the role of histamine, see the articles on this topic in the science section, www.watercure.com/Topics10.htm or read my book ABC of Asthma, Allergies and Lupus.

F. Batmanghelidj, M.D.