Last Updated on January 31, 2023 by Andre Panagos M.D.
Water is critical to your well-being
Research into the basic concepts of dehydration still leaves a lot of questions unanswered.
Your body is a giant bag of water
The billions of biochemical reactions your body needs to function normally are vitally dependent on the efficient flow of water. Water comprises up to 75% of the total body weight in infants and falls to 55% in the elderly (Hooper 2014). Water makes up 85% of the total weight of the brain (Kleiner 1999). More than half of the water within our body is found in the cells with the remainder in the blood and lymph vessels. Water is required for energy production, digestion, transportation, elimination, and temperature regulation. Water not only allows these biochemical reactions to occur, but it also fills the space in and between cells and is an important part of of the collagen fibers that form the structure of your body.
You are dehydrated most of the day
Dehydration is very widespread in society (Begum, 2010). Surveys show that up to 75 percent of Americans don’t drink enough water daily (Ericson, 2013). Eighty-two percent of a sample population and up to 95% of the elderly within a sample in Australia failed to meet adequate intake values for total water intake (Sui 2016). The average total intake of fluid was 1-1.3 liters per day depending on age groups. Water accounted for about one-half of daily fluid intake with the remainder originating from foodstuffs like fruits and vegetables (Bellisle, 2010). The hypothesis is that people lose their thirst sensation beginning as early as 20 years of age. Also, cellular absorption of water from blood vessels also decreases with aging. These two changes results in progressive dehydration starting from early adulthood.
Signs of dehydration
A dry mouth or skin tenting on the back of your hand are later signs of dehydration. Dehydration of as little as 2% loss of body weight results in impaired physiological and performance responses (Kleiner 1999). If the body loses one liter of water, function becomes impaired and thirst, flushing, dark-colored urine, dry mouth, fatigue, and weakness occur; if down 5 liters, fatigue and dizziness develop, sweating decreases and the core temperature rises; a loss of 15 liters can lead to muscle spasms, confusion and could be fatal (Kamler, 2005, Rothenberg, 2008).
Effects of dehydration on the body
Dehydration impairs your metabolism and cell function
Proper metabolism is dependent on chemical reactions that critically depend on water. The flow of water through the cell membrane and mitochondria creates energy that is stored in the form of adenosine triphosphate (ATP). The hydrogen and oxygen molecules from water (H2O) are used by an enzyme called ATP Synthase to convert the ADP to ATP (Jonckheere, 2012). The mitochondria produce less ATP if there is less intracellular water (Robin, 1976). When a cell does not have enough energy to repair itself, the cell breaks down or ruptures. When it ruptures, enzymes are released that cause inflammation and damage to adjacent cells and tissues (Robin, 1976). Water is important for clearing out toxins, otherwise chronic inflammation develops within the cells which eventually spills over into the blood vessels and the rest of the body.
Impaired performance occurs with sudden fluid losses
Out of a total water volume in our body of 50 liters, we lose at least 2 liters of water a day from normal daily body maintenance (Kamler, 2005). Water losses via the skin can range from 0.3 liters per hour in sedentary conditions to 2.0 liters per hour in high activity in the heat. Water intake requirements range from 2.5 liters to slightly over 3 liters per day in adults under normal conditions, and can reach up to 6 liters per day in extremes of heat and activity (Hooper 2014). Simply sitting in a hot climate can cause the body to lose at least 5 liters of water per day. Dehydration appears to have a negative impact on physical performances that are longer than 30 seconds in duration. Exercise performance is impaired even when an individual is dehydrated by as little as 2% of body weight. Even though there is no significant negative impact on tasks lasting less than 15 seconds in duration, a state of proper hydration is suggested to be maintained during all physical activities (Carlton 2015). The capacity to perform high-intensity exercise, which results in exhaustion within a few minutes, is reduced by as much as 45% with pre-activity dehydration (Carlton 2015).
Dehydration promotes inflammation
Histamine formation and release is directly connected to the concentration and viscosity of internal solutions (Goldstein, 1977). Pain results from local chemical changes in the area surrounding the nerve. When water is not present to clear the cellular metabolic waste, it builds up injuring the surrounding tissues. HIstamine release can also cause symptoms associated with asthma and allergic reactions (Haas, 2008).
Dehydration can cause weight gain
Thirst is sometimes interpreted by the body as hunger which can lead to overeating (Batmanghelidj, F, 2005). Obese individuals behave in ways that lead them to be inadequately dehydrated. Obese individuals have higher water needs than nonobese individuals, because water needs depend upon metabolic rate, body surface area, and body weight (Chang, 2016). Proper hydration leads to an increase in metabolism from an increase in cell volume and decreased feeding resulting in weight loss. This hypothesis derives from an association between chronic dehydration and raised levels of the hormone angiotensin which is associated with many chronic diseases, such as obesity, diabetes, cancer, and cardiovascular disease (Thornton, 2016).
Dehydration causes joint and cartilage damage
Joint cartilage contains up to 80% water (Sophia Fox, 2009). Water acts as a lubricant which allows the two opposing joint surfaces to glide freely over each other. Water acts as an adhesive material in cellular architecture to keep structures firm and intact. Motion causes cartilage cells to peel away and die but cells underneath take their place. With proper hydration, this friction damage is minimal. With dehydration, there is greater abrasive damage which over time results in osteoarthritis. Exercise creates an intermittent vacuum within the joints allowing fluid and critical nutrients to flow into the joint cavity from the surrounding bone. The Intervertebral joints and discs in the spine are also dependent on the hydraulic properties of water. The majority of the weight of the upper body is supported by the volume of water within the center of each intervertebral disc. The center of the disc, called the nucleus pulposus, forms a natural ball bearing type structure which allows for 360 degrees of motion with little friction. Collagen fibers become stiffer with dehydration (Kemp, 2012) which increases their susceptibility to injury or damage.
Swollen joints and ankles may be a sign of dehydration
Structures that do not have direct blood flow, such as the intervertebral discs and joint cartilage are impacted first in chronic dehydration (Wang, 2013). The nerves within the cartilage and soft tissues of the joint increase arterial blood flow resulting in eventual joint swelling (McDougall, 2006). Severe dehydration results in lower leg swelling and water retention because the body increases the extracellular fluid to maintain the fluid within the blood vessels and provide enough to maintain kidney filtration. If more pressure is needed to drive water into the cells this is called hypertension. This process is more efficient when lying horizontally, as the fluid within the legs progresses towards the torso without fighting gravity. Hence the need to go to the bathroom at night with chronic dehydration. This cannot be treated by drinking too much water initially as it may overwhelm the body. Slow increased water intake over time allows the body to rehydrate.
Dehydration can elevate your cholesterol level
High cholesterol is a defense mechanism that protects cells from dehydration (Campbell, 1994). The waxy fatty layer prevents water from leaving the cell and concentrated blood prevents the diffusion of water into the cell. If you do not drink water before you eat, food digestion will injure the cells in the blood vessels and gastrointestinal tract. Water is required for food digestion including the production of hydrochloric acid to break down food. If you have a history of heartburn, it may be caused by too little hydrochloric acid in the stomach which does not completely close the lower esophageal sphincter (Tsoukali, 2103). The liver also needs water to process the components of the food. Following a meal, the cells of the large blood vessels, heart and brain that are first exposed to the highly concentrated viscous blood are the large blood vessels and capillaries of the heart and brain. So cells need to protect themselves from this damage. The body will make less cholesterol if the cells remain fully hydrated (Campbell, 1994).
Dehydration stresses your body and the brain
About 20% of blood circulation is used by the brain. The brain uses glucose for energy. The body maintains normal plasma glucose levels by either stimulating appetite or converting stored starch and proteins into sugar by a liver process called gluconeogenesis. The body needs muscle activity to maintain normal function. If brain requires more energy (used more, or in times of stress) and the body is not used proportionally to supply the brain with sugar needs, a person will eat larger quantities of food more often and if the muscles are not active become stored as fat. With increased water, this storage does not happen. With stress, the body becomes dehydrated and initially draws water from inside the cells to make up the deficit.
Dehydration can cause high blood pressure
The renin-angiotensin system is activated to retain water and promote the absorption of salt in the presence of dehydration. It also tightens the capillary beds and overall vascular system until all tissues are well-hydrated. Tightening the vessels increases the pressure within the vessels resulting in a condition known as hypertension. Exercise causes relaxation of these blood vessels which results in greater capillary volume which can lower blood pressure. With any stress, the body uses water to break down protein, glycogen, and fats to create energy. If there is pre existing kidney damage, the kidneys have to work harder to filter the blood which causes greater kidney damage. If this process continues over years, the result can be kidney failure (Hooper 2014).
Drink pure and clean water to rehydrate
Use a carbon filter system or reverse osmosis system to remove pesticides, chlorine, fluoride, and heavy metals. Beware distilled water as it will pull electrolytes out of you body. Use a system that specifically removes fluoride as there is conflicting information about its safety. Chlorine is a gas and it can evaporate from a glass of water after it is left to stand for 30 minutes. We get water not only directly as a beverage but from food as well, with fruits and vegetables containing the most water content (Hooper 2014). It is important not to drink too much water. Over hydration can be dangerous by diluting your blood electrolytes which can cause a condition called hyponatremia. Hyponatremia happens most often in endurance races such as marathons in individuals who drink too much water during the race (Rothenberg, 2008). Proper hydration results in colorless urine.
Salt is very important for hydration
It is important to supplement drinks with additional salt or electrolyte solution when excessive sweating is experienced (Hooper 2014). Salt is thought to be a strong antihistamine (Batmanghelidj, 2005). Salt is also very important for the the kidneys for water filtration.
Some researchers believe that osteoporosis is due to a shortage of water and salt within the body (Granke, 2015). Approximately 27% of the salt content within the body is stored in bone. The salt is used to strengthen the bones.
Unrefined sea salt is a better choice as it also contains trace elements. You need approximately 3 g of salt (half a teaspoon) per 10 glasses of water per day. Exercise and sweating as well as hot climates require greater salt intake.
Check with your doctor if you have kidney disease or heart failure before increasing salt intake.
If you feel that your skin or ankles are beginning to swell, reduce salt intake and increase water intake for several days until the swelling disappears. You should also increase your muscle activity and not stand or sit in one position for too long.
You need to regularly drink water to prevent dehydration
To maintain proper hydration, the average sedentary adult male must consume at least 3 liters (12 cups) of fluid per day, and the average sedentary adult woman at least 2.2 liters (9 cups) of fluid per day, in the form of non-caffeinated, non-alcoholic beverages, soups, and foods (Kleiner 1999). The current guidelines for water intake according to the Institute of Medicine adequate intake standards are higher at 3.7 liters (15 cups) per day for adult men and 2.7 liters (11 cups) per day for adult women (Chang, 2016). One to three glasses 30 minutes before a meal, One to two glass two and a half hours after each meal. Thirst should always be satisfied. The thirst mechanism becomes more efficient with increased water intake. Drinking at least one glass of water 30 minutes before a meal prevents the blood from becoming too concentrated due to food intake. Concentrated blood draws water from the cells. It takes much longer to rehydrate with increasing age (Phillips, 1984). Overweight people should drink half an ounce of water per pound of body weight divided per day (Chang, 2016).
Athletes need even more water to stay hydrated
An athlete training in a warm environment can lose 1.5 liters per hour. The goal is to stay within 2% of your pre-exercise body weight. You should drink every 10-15 min when exercising. Plan on replacing two cups of fluid for every pound lost, or half a cup every 10-20 min. A large volume of fluid such as ½ liter (2 cups) should be consumed immediately after exercise, with ¼ liter (one cup) of fluid every 15 minutes until at the pre-exercise body weight. Fluid should contain carbohydrate (return stored glycogen to the muscles) and trace minerals or sea salt. Avoid coffee, tea, soda, chocolate as they increase water loss. Urine should be clear. (Benardot, 2000). The easy way to titrate your electrolyte intake is by your bowel movements. If you start to develop loose stools when you’re adding electrolytes, you’re probably over your natural limit.
Intensive three-day hydration protocol
Start by drinking ½ cup of water every 30 minutes from about 7am to 7pm. Add electrolytes to every other dose. Then they can remove what they need to before they go to sleep 2-3 hours later. (Mercola, 2018).
Exercise builds a body that can resist dehydration
Exercise increases muscle mass resulting in an increase in the body’s ability to maintain a water reserve (Bak, 2016). Exercise also promotes joint motion which protects the cartilage layer and the tissues within the joint.
Nonsteroidal anti-inflammatory drugs (NSAIDs) and dehydration are dangerous
You should consider drinking at least two liters of water within a 24 hour period for several days before considering the use of nonsteroidal anti-inflammatory drugs (NSAIDs). NSAIDs inhibit prostaglandins, which are hormones that regulate blood flow to the kidneys. With prior dehydration and especially in children or the older population, nonsteroidal anti-inflammatory drugs can cause kidney damage or even failure
Regular caffeine and alcohol will dehydrate you
Chronic and severe dehydration from regular intake of caffeine and alcoholic beverages increases histamine secretion along the lining of the nerves promoting inflammation and damaging the local cells. Excess caffeine depletes ATP-stored energy. Dehydration is the most important stressor in the body. Caffeine has addictive properties in the brain and acts as a diuretic and a dehydrating agent. Many people drink several cans of soda and never feel fully satisfied as they become dehydrated. People confuse the feeling of thirst with hunger and end up eating more food. Caffeine lowers the threshold of control of the stored ATP energy. The sugar in soda satisfies some of the brain’s requirement for energy.
ICD-10-CM code E86. 0 Dehydration
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