The Functions of Water in a Human Body

Abstract

How much water we really need depends on water functions and the mechanisms of daily water balance regulation. The aim of this review is to describe the functions of water balance and highlight the new recommendations with regard to water requirements. Water has numerous roles in the human body. It acts as a building material; as a solvent, reaction medium and reactant; as a carrier for nutrients and waste products; In thermoregulation; and as a lubricant and shock absorber. The regulation of water balance is very precise, as a loss of 1% of body water is usually compensated within 24 h. Both water intake and water losses are controlled to reach water balance. Minute changes in plasma osmolarity are the main factors that trigger these homeostatic mechanisms. Healthy adults regulate water balance with precision, but young infants and elderly people are at greater risk of dehydration. Dehydration can affect consciousness and can induce speech incoherence, extremity weakness, hypotonia of ocular globes, orthostatic, and hypotension.

Human water requirements are not based on a minimal intake because it might lead to a water deficit due to numerous factors that modify water needs (climate, physical activity, diet and so on). Water needs are based on experimentally derived intake levels that are expected to meet the nutritional adequacy of a healthy population. The regulation of water balance is essential for the maintenance of health and life. On an average, a sedentary adult should drink 1.5 L of water per day, as water is the only liquid nutrient that is really essential for body hydration.

Introduction

Water is defined as an essential nutrient because it is required in amounts that exceed the body's ability to produce it. All biochemical reactions occur in water. It fills the spaces in and between cells and helps form structures of large molecules such as protein and glycogen. Water is also required for digestion, absorption, transportation, dissolving nutrients, elimination of waste products and thermoregulation.Water accounts for 60-80% of body weight, depending on lean body mass. On average, men have a higher lean body mass than women and higher percentage of body mass as water than in women. The relative mass of water decreases in both men and women with age. Human requirements for water are related to metabolic needs and are highly variable. They depend to some extent on individual metabolism.Water is essential to life and nutritional health.

Humans can live for several weeks without food, but we can survive only a few days without water. Water makes up a large percentage of the body, in muscles, fat cells, blood and even bones. Every cell, tissue and organ requires water to function properly. Water transports nutrients and oxygen to the cells, provides a medium for chemical reactions to take place, helps to flush out waste products, aids in maintaining a constant body temperature keeps the tissues in the skin, mouth, eyes, and nose moist.

Water Function(s)

Water, as previously mentioned, is an essential nutrient. This nutrient has many functions throughout the body and without it, you would die. Every cell, tissue, and organ in your body requires water to function properly. You could survive longer without food than you could without water. Your body is made up of 60%-70% of your body weight, depending on other factors. The list of the functions of water is a pretty lengthly one being that it plays a role in all of the systems of the body. Water helps to regulate our body temperature, protects and cushions our vital organs, moistens oxygen for optimal lung function, helps the liver remove waste, carries nutrients and oxygen to the cells and more. Take a lookout the figure below for more functions of water. Water should be consumed daily in your recommended serving amount depending on your weight.

Water and Weight Loss

Switching to drinking water will help to boost your metabolism which in turn will help you lose weight. Water is also said to be an appetite suppressor so you don’t eat as much food. Next time you eat a meal, drink some water beforehand and you will consequently eat less food. Also water aids in helping you to cleanse your body of waste. When your body is dehydrated, it can’t burn fat.

Water and Quitting Smoking

As mentioned already, water helps with digestion. Smokers often suffer from constipation when on their journey to quit smoking. People who are quitting smoking are also encouraged to to exercise and that requires water intake to stay hydrated. Keeping your hands busy when you have a sudden urge for a cigarette is very helpful and drinking water improves alertness and the ability to concentrate.

Water Deficiency

Dehydration is the deficiency of water in the body. Dehydration, if severe enough, can be fatal. As dehydration comes upon the body, the amount of fluid present in the body obviously decreases. This causes a decrease in the blood flow to vital organs including the kidneys. Individuals who are at- risk for dehydration include athletes, people at higher altitudes, and older adults. Surprisingly, 75% of Americans are currently dehydrated. If you lack water you are at a higher riskier a urinary tract infection. The importance of water is now being talked about more. Some of the common causes of dehydration include vomiting, diarrhea, urinating too much because of medical problems such as diabetes, taking medicines that make you urinate, and excess sweating. These should only be seen as causes if they are excessive but sweating and urinating normally is perfectly fine. Mild to moderate symptoms include being very thirsty, having a dry mouth, and urinating less. Symptoms of severe dehydrated include lightheadedness, fainting, shock, confusion, passing out, death, rapid heartbeat, and rapid breathing.

Water Toxicity

Water Intoxication is the disruption of brain function due to drinking too much water. Water intoxication results from the swelling of cells. Excess fluid accumulation in the brain is called cerebral edema. People at-risk for water intoxication include soldiers, endurance sports athletes and schizophrenia patients. Water intoxication is rare but it is now being brought to awareness because some people just know water is good for you and not that there is a limit on how much you should consume. Water intoxication has several symptoms. Some first symptoms of water intoxication include headaches, nausea, excessive salivation and vomiting. Don’t self-diagnose yourself but if you are experiencing these symptoms frequently, you should definitely go to the doctor before it worsens. Severe cases of taking in too much water include coma, seizures, collapses, confusion, double vision, drowsiness, difficulty breathing, etc. If water intoxication goes untreated, it could lead to death.

Screening, Assessment and Monitoring There are different types of ways to screen, access, and monitor water deficiency and toxicity. Using the ABCD (Anthropometric, Biochemical, Clinical, and Dietary) Nutrition assessment it shows the different methods. To check by using Anthropometric you could focus on the weight of the person. To check using Biomedical, you could check by the color of their pee or a urine test. To test by using Fields Chasity Hardnett Jailah Human Nutrition, FALL 2019 5 clinical you could check by the health of one’s skin. Lastly, by dietary you could check by the amount of water one drinks.

Implications for Health Promotion and Disease Prevention

Water is a very important to your everyday diet. Although we are constantly told 8 glasses a day, you should check the amount of water for your body weight. Once you know what your intake should be, monitor how much you drink. If you don’t quite meet your goal start setting a goal to drink everyday. There are also water bottles with hours of the day that encourage you to drink your goal amount. Be aware of the symptoms involved in dehydration and water intoxication so you always drink your recommend amount. If you feel you are having symptoms, get tested it’s always better safe than sorry. The color of your urine is a great indictor for water deficiency and toxicity. Remember water is essential to life and it helps all systems of our body function. Don’t forget to have regular check-ups at the doctor.

Conclusions

Water, a vital nutrient, has numerous critical roles in the human body. It acts as a building material; as a solvent, reaction medium, reactant and reaction product; as a carrier for nutrients and waste products; in thermoregulation and as a lubricant and shock absorber. Consequently, the optimal functioning of our body requires a good hydration level. The regulation of water balance is very precise and is essential for the maintenance of health and life.

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