Dehydration

Dehydration happens when the body loses too many fluids. Dehydration can occur when the body is deprived of fluids through illness, diarrhea, vomiting, sweating, exercise, or not consuming enough water. Some symptoms of dehydration are nausea, dizziness, feeling lightheaded, and fainting. People who are at risk of dehydration are babies, small children, and older adults.

The body consists of 60% water so being properly hydrated allows the body to function. Water is lost during breathing, sweating, urination, and bowel movements. Lack of water in our body deprives oxygen from being delivered in the bloodstream, along with nutrients to cells. Water can move between body components to equalize water in cells, blood, and other body parts. This action is called osmosis. "The body regulates amounts of water in each compartment by adjusting the concentration of dissolved particles and relying on osmosis to move the water." (Grosvenor & Smolin, 2006). Blood pressure will cause water movement to be pushed from blood into cells. If pressure is low, water returns to the body by osmosis.

Water has many functions in the body. It cleans internal body surfaces, along with external surfaces of the body. Water produces tears, which lubricates the eyes, produces saliva to making eating easier, and helps in creating fluids to lubricate joints. Since water can resist compression, it cushions body parts, like eyeballs, joints, and even a fetus in a pregnant woman. The amniotic sacs consist of water. Blood consists mainly of water and delivers oxygen and nutrients to cells, while sending waster products to kidneys and lungs for elimination. Water also works in a chemical reaction to help regulate body temperature. "Water works as a solvent in glucose, amino acids, minerals, and other substances needed by body cells." (Grosvenor & Smolin, 2006). Water regulates body temperature to keep the body's temperature constant. Blood helps regulate body temperature by increasing or decreasing heat loss at the surface of the body.

The body monitors the fluids it needs to function. The feeling of being thirsty is signaled by a dry mouth, along with a signal from the brain. The brain senses a decrease in fluids, along with substances that are not dissolved still in the blood. The lack of saliva in the mouth also creates the need for fluids. The lack of water in the body will cause the kidneys to decrease in their functions in order to conserve water for the body. When high concentrations of dissolved particles are in the blood, a hormone called anti-diuretic hormone (ADH) tells the kidneys to reabsorb water, eliminating water loss through urine. When the body is hydrated, ADH decreases allowing water to be released through excrement of water waste. Waste eliminated in urine includes breakdowns of proteins, fats, phosphates, sulfates, and electrolytes.

Sodium, potassium, and chloride are electrolytes in the body whose function is to help regulate fluid balances and maintain acid-based balances. Electrolytes are used in nerve conduction and muscle contraction by movement of sodium and potassium ions across nerve cell membranes. Sodium is outside a cell, while potassium is inside the cell. When a nerve is stimulated, sodium moves into the cell causing a nerve impulse. When a nerve signal travels to a muscle cell, the same process occurs, triggering a muscle contraction. Sodium combined with chloride causes an increase in sodium concentration, making a person thirsty, along with having water retention. As the body eliminates the extra sodium, water retention