Life on the planet Essay

Water is a vital element for the survival of life on the planet. In human beings, water comprises fifty to seventy percent of an adult’s body weight. In humans the abstinence from water results in death in a few days. Water is lost from the human body loses due to urination, sweating and respiration. The body’s water content has to be maintained by regular intake of water and people who fail to consume sufficient water become dehydrated. They develop headaches, tiredness and loss of concentration. Persistent dehydration results in serious health problems such as constipation and gall bladder stones (Hicks, 2005). The human body gets water from water in the pure form and beverages, solid foods such as fruits and vegetables and through the chemical processes in the body. According to the British Dietetic Association, an average adult must consume at least two and half liters of water per day. Of this, nearly two liters should be through beverages. During summer the intake of water has to be increased. Physical activities also require the consumption of more water. It is the major ingredient of all juices and carbonated drinks contain sixty five percent, diluted squashes eighty six percent and fruit juices ninety percent water. However, drinking plain water is the most effective means of compensating for depleted body fluids (Hicks, 2005). Water is the chief element of human body and its essential nutrient. In fact, a human being can survive without food for a considerable period of time but cannot survive for more than a week without water. Water is essential for breathing as it bedews oxygen and supplies it to every cell in the body. Water makes the skin more shiny and supple. It controls the body temperature and discards toxins and other waste material from the body. It distributes important nutrients throughout the body and helps in removing waste materials from the kidneys and the large intestine. The digestive mechanism is enhanced by water and it is essential for the development and maintenance of good muscle tone. It protects and cushions vital organs and acts like a lubricant for the joints by contributing to the special fluids which protect bones from friction and erosion. Water increases the activity of the brain and improves mental quickness in reflex responses (Dr. Susan Kleiner Ph. D. ). Water is a vital nutrient which contributes to every function of the body. It acts as a vehicle in transporting essential nutrients to the cells and waste material out of them. Water is necessary for the functions of digestion, absorption, circulation and excretion and for the absorption of water – soluble vitamins. It is essential for regulating the body temperature (Functions of Water in the Human Body). The water in saliva allows foods to slide smoothly down the esophagus and the watery fluids dissolve enzymes, hormones and coenzymes. Water acts as a solvent for waste materials like urea, carbon dioxide and other electrolytes in the body. It plays a major role in Hydrolysis in which water molecules divide into hydrogen H+ and hydroxyl OH- ions. This chemical process forms the basis for the reaction of substances in the human body. For instance, sucrose is hydrolyzed into fructose and glucose. Moreover, water serves as a catalyst in intercellular reactions and maintains the electrolyte balance in the body (Water in the Body). Insufficient water results in dehydration, formation of kidney stones and particularly in women, urinary tract infections. Its scarcity affects physical and mental performance and the function of the salivary glands. Dehydration causes kidney function disorders, harmful changes in hormonal levels, chronic illness and limited mobility (Dehydration). Electrolytes are obtained from food and are absorbed in the intestines. The kidneys maintain the required electrolyte levels in the body. These electrolyte levels are affected by diseases and dehydration. Potassium, the chief cation in the intracellular fluid, plays an important role in activating enzymes and processing and retaining carbohydrates. It acts as medium for transmitting nerve impulses to the heart and skeletal muscles. Its deficiency leads to major health problems. Its depletion is caused by the use of diuretics like thiazides that are used in the treatment of hypertension and heart ailments, excessive perspiration, repeated enemas, trauma, diabetes, diseases of the intestinal tract and disease of the kidney due to the use of tetracycline and excessive intake of licorice. The loss of potassium causes weak pulse, faint heart sounds, low blood pressure and fatigue. Loss of large amounts of potassium results in death (Hecht, 1986). Magnesium is another electrolyte that is present in the intracellular fluid. It helps in muscle contraction, nerve transmission and acts as catalyst for enzymes. Deficiency of magnesium results from an improper diet, diarrhea, steatorrhea, alcoholism, diabetes, pancreatitis, damage of kidneys and diuretics. Functional disorder of kidneys raises the magnesium levels of the body and persons with kidney ailments have to avoid laxatives and antacids, which contain magnesium. This is due to the fact that excessive levels of magnesium lead to depressed reflexes, paralysis of muscles and decreased respiration (Hecht, 1986). Sodium is another important cation in the extracellular fluids, whose main function is to maintain the body’s fluid balances. Low sodium body levels result from dehydration, sweating, the use of diuretics and diarrhea, which result in muscular weakness, anxiety and convulsions. Inadequate water intake and malfunction of the kidneys increases the sodium concentration. Depletion of sodium levels in the body result in dry mucous membranes, flushed skin, rise in body temperature, dry eyes and un – sated thirst (Hecht, 1986). Chloride is the major anion of the extracellular fluid. It is important for muscle contraction, balancing the fluid levels in the cells and maintaining the acid – base balance of extracellular fluid. In order to prevent the accumulation of bicarbonate, there should be a sufficient supply of chloride ions (Hecht, 1986). Calcium is present in the extracellular fluid and is important for nerve impulse transmission, contraction of muscles and the clotting of blood. It mainly exists in the body in the non – ionized state in the bones and the teeth. Pancreatitis, chronic kidney disorders and the surgical removal of the parathyroid tissue decrease the ionized calcium levels. Insufficient calcium levels cause abdominal and muscle cramps, tingling of the finger tips, numbness and overactive reflexes. Excessive calcium levels in the body cause a significant loss of appetite, nausea, weight loss, kidney stones and body pains (Hecht, 1986). Alcohol induces water loss by suppressing the production of the anti – diuretic hormone vasopressin, which works on kidneys to concentrate urine by increasing the reabsorption of water and electrolytes into the body. Suppression of this hormone results in the increased loss of body fluid through urination leading to dehydration. Alcohol – induced loss of water also results in the loss of magnesium, potassium, calcium and zinc, which are essential for maintaining the fluid balance of the body and muscular activity. Researchers in the UK studied the effect of alcohol on hydration and electrolyte balance after exercise – induced dehydration. They found that the volume of urine produced in the consequent six hours of rehydration had increased on par with the intake of alcohol. However, the rate of increase of the blood plasma during rehydration was considerably slower (Hamilton). Coffee and tea are rich in caffeine or trimethyl xanthine. Caffeine stimulates the central nervous system. It blocks the binding of adenosine with the nerve cells, which enhances nerve activity and leads to the release of epinephrine. It also increases the release of the neurotransmitter dopamine. The ergogenic properties of caffeine promote lesser muscle activity by reducing glycogen thereby allowing more calcium into muscle cells, which would enhance the power of muscle activity. Caffeine is a diuretic and in higher doses results in heavy water loss through urination. It also increases the blood flow to the kidneys and reduces the reabsorption of sodium by the body (Hamilton). Dehydration is prevented by drinking eight glasses of water per day and abstaining from caffeinated drinks and alcoholic beverages. The common cause of dehydration is due to the loss of fluids from body as a result of gastrointestinal ailments, diarrhea and vomiting. In order to compensate for the lost fluids large amounts of water and fruit juices have to be consumed. Wearing loose fitting clothes keeps the body cool and prevents sweating. Those who participate in sports, have to drink water and fruit juices at regular intervals. Moreover, people should avoid the consumption of coffee, tea and other caffeinated beverages, because they act like diuretics (Gavin, 2006). In the absence of adequate hydration, true health remains a chimera. The minimum daily intake of water has been stated to be half as many ounces as there are pounds in one’s body weight. The reason for this is that in order to function properly and optimally, every organ in the body requires water to a major extent. A human being’s body consists mostly of water and in its absence life is not possible. References Dehydration. (n. d. ). Retrieved June 30, 2007, from http://www. betterhealth. vic. gov. au/bhcv2/bhcarticles. nsf/pages/Water_a_vital_nutrient? open Dr. Susan Kleiner Ph. D. , R. (n. d. ). Health & Hydration . Retrieved June 30, 2007, from http://www. calistogawater. com/health/ Functions of Water in the Human Body. (n. d. ). Retrieved June 30, 2007, from http://www. resultsproject. net/water_functions. html Gavin, M. L. (2006, January). Dehydration. Retrieved June 30, 2007, from http://www. kidshealth. org/teen/safety/first_aid/dehydration. html Hamilton, A. (n. d. ). Caffeine dehydration : Caffeine and alcohol – just how dehydrating are they? Retrieved June 30, 2007, from http://www. pponline. co. uk/encyc/caffeine-dehydration. htm Hecht, A. (1986, January 1). ELECTROLYTES. Retrieved June 30, 2007, from Electrolytes; the charge in the body’s power system. : http://www. encyclopedia. com/doc/1G1-4293240. html Hicks, R. (2005, September). Why do we need water? Retrieved June 30, 2007, from bbc. co. uk: http://www. bbc. co. uk/health/healthy_living/nutrition/drinks_water. shtml Water in the Body. (n. d. ). Retrieved June 30, 2007, from http://www. dehlgroup. com/wbody. html