Chloride

About Chloride

Chloride is the most abundant negatively charged ion in the fluid outside cells and works closely with sodium and potassium to maintain fluid balance, blood volume, blood pressure and acid base balance. Parietal cells of the stomach secrete chloride as part of hydrochloric acid, which aids digestion and protects against ingested microbes. Chloride also takes part in the chloride shift, in which red blood cells exchange chloride for bicarbonate to help carry carbon dioxide in the blood. Most dietary chloride comes from sodium chloride, ordinary table salt, so intake generally follows salt consumption and deficiency from diet alone is rare. Low blood chloride can occur with prolonged vomiting, heavy sweating, some diuretic use and certain kidney conditions, and is associated with metabolic alkalosis. In the late 1970s some infant formulas sold in the United States lacked adequate chloride, causing deficiency in infants and contributing to the passage of federal infant formula legislation. Cystic fibrosis results from defects in a chloride channel known as CFTR.