What Are Electrolytes?
Electrolytes are the smallest of chemicals that are important for the cells in the body to function and allow the body to work. Electrolytes such as sodium, potassium, and others are critical in allowing cells to generate energy, maintain the stability of their walls, and to function in general. They generate electricity, contract muscles, move water and fluids within the body, and participate in myriad other activities.
The concentration of electrolytes in the body is controlled by a variety of hormones, most of which are manufactured in the kidney and the adrenal glands. Sensors in specialized kidney cells monitor the amount of sodium, potassium, and water in the bloodstream. The body functions in a very narrow range of normal, and it is hormones like renin (made in the kidney), angiotensin (from the lung, brain and heart), aldosterone (from the adrenal gland), and antidiuretic hormone (from the pituitary) that keep the electrolyte balance within those normal limits.
Keeping electrolyte concentrations in balance also includes stimulating the thirst mechanism when the body gets dehydrated.
Electrolyte: Sodium (Na)
Sodium is most often found outside the cell, in the plasma (the non-cell part) of the bloodstream. It is a significant part of water regulation in the body, since water goes where the sodium goes. If there is too much sodium in the body, perhaps due to high salt intake in the diet (salt is sodium plus chloride), it is excreted by the kidney, and water follows.
Sodium is an important electrolyte that helps with electrical signals in the body, allowing muscles to fire and the brain to work. It is half of the electrical pump at the cell level that keeps sodium in the plasma and potassium inside the cell.
Medically Reviewed by a Doctor on 10/25/2016
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