Introduction Water is an important part of the human body, so much so that nearly 60% of adults’ body weight is made up of water. A human can go many days without food and other nutrients without feeling any serious effects, but if you go even a day without water symptoms of dehydration can begin to appear. A person can even experience symptoms of dehydration after just one hour of exercise on a hot day. Dehydration is Excessive loss of water resulting in depletion of body fluids (, 2006). The effects of dehydration can be very serious in humans and can even lead to death. This paper will examine the functions of water in the body and what happens when the body does not receive the water it needs.
Water in the Body Water provides many functions in different areas of the body. Water is used by the body to help dissolve many substances that it needs such as glucose, minerals, and amino acids. Water also helps maintain the proper level of acidity in the body. There are many chemical reactions that take place in the body and water is a part of a number of them. Examples of these include reactions that join smaller molecules together and break larger molecules apart. Reactions of metabolism also occur in water which helps fuel the body. Water also plays a major role in maintaining the body’s temperature. Water holds heat and changes temperature at a slow rate which helps the body maintain a steady temperature. Water in the blood also helps regulate body temperature by increasing or decreasing the amount of heat lost at the body’s surface. When you exercise your skin can become red and you usually sweat. This happens because the blood vessels in the skin dilate so the blood flows close to the surface where it is released into the air. When it is cold outside like it is in the winter, the blood vessels in the skin contract restricting the blood flow at the surface in an effort to conserve heat. When a person is thirsty, that person’s body is telling them to consume water to bring their levels back up. The urge to drink water is signaled from the brain as well as from dryness in the mouth. Unfortunately water cannot be stored in the body and it is constantly lost. If it could be stored, the body would almost always have the supply of water that it needs. When the body does not get the amount that it needs it can have detrimental effects on the body. The body can only survive without water for a few days, but the effects can be felt much sooner than that. Men and women need to consume different amounts of water to stay healthy, but each person’s needs vary based on their diet, what climate they live in, and how much physical activity they perform each day. When there is not a sufficient amount of water in the body a person will can begin to experience signs of dehydration. Dehydration can start with something as simple as thirst, but when the water supply in the body is not replenished dehydration can become life-threatening. The initial symptoms of dehydration include headache, thirst, fatigue, dry mouth, and dark-colored urine. As the body continues to be deprived of water, more severe symptoms start to show such as nausea, disorientation, and difficulty concentrating. If nothing is done to restore the water levels in the body it can eventually lead to death. Electrolytes play a vital role in keeping the human body alive. Electrolytes are substances that separate in water to form positively and negatively charged ions that conduct an electrical current. Sodium, potassium, and chloride are the types of electrolytes found in the body. Sodium and Potassium are positively charged ion and are a part of every nerve impulse that is responsible for muscle contraction and nerve conduction in the body. Although they are both positively charged ions, potassium is concentrated inside the cells and sodium is concentrated outside of the cells. Sodium also aides in regulating blood pressure in the body. When there is a drop in blood pressure, the kidneys release hormones and proteins that affect the amount of sodium and water that is retained by the kidneys. The first thing to be released in an enzyme called rennin, which helps form the compound Angiotensin II. The compound causes blood vessels to constrict as well as stimulating the release of the hormone aldosterone which triggers the kidneys to retain sodium and water. This chain of events helps return blood pressure in the body to a normal level. Sodium and chloride is also found in many of the foods we eat, but not always in a natural way. Salt is added to many processed food as a preservative which helps fight bacteria growth. With such an abundance of processed foods on the market today, many people have a high sodium intake and a low potassium intake in their diets. Potassium is found more in fruits and vegetables as well as fresh meat and milk products. Many people do not consume the suggested daily intake of potassium because they do not eat many fruits or vegetables. Too much or too little potassium can be extremely harmful to someone’s health. When a person dies suddenly from starvation or from a disease like anorexia nervosa, it can potentially be from having a potassium deficiency that causes the heart to stop. The same can occur if there is too much potassium in the blood, though a healthy person with normal kidney function should not face this problem. In addition, too much sodium has been known to increase blood pressure. Alcohol acts as a diuretic which causes the body to urinate more frequently which can lead to dehydration. Alcohol induced dehydration also causes the loss of the electrolyte potassium as well as other minerals. Caffeine on the other hand has no real dehydrating effect on the body. There is usually enough water in caffeinated beverages to prohibit dehydration from occurring but water is still the safest way to ensure that the body stays hydrated. To ensure proper hydration levels are maintained, people should consume water every day to stay hydrated and maintaining a proper diet of fresh foods and vegetables.

Grosvenor, M. B., & Smolin, L. A. (2006). Nutrition: Everyday choices. Hoboken, NJ: John Wiley & Sons.