TABLE 4.

Functions and Food Sources of Minerals and Trace Elements

MineralChief Functions in the BodySignificant Sources
CalciumBone and teeth formation; involved in normal muscle contraction and relaxation, nerve functioning, blood clotting, and blood pressureMilk and milk products; small fish (with bones); greens; legumes; calcium-fortified tofu; calcium-forti fied juices; calcium-fortified rice, soy, or potato milks
ChloridePart of hydrochloric acid found in the stomach, necessary for proper digestionSalt, soy sauce; moderate quantities in whole, unprocessed foods, large amounts in processed foods
ChromiumCofactor for insulinMolasses, nuts, whole grains, and seafood
CopperCofactor for enzymes; necessary for iron metabolism; cross-linking of elastinLiver, shellfish, whole-grain cereals, legumes, and nuts
FluorideStructural component in calcium hydroxyapatite of bones and teethSeafood, meat, fluoridated water
IodideA component of the thyroid hormone, thyroxin, which helps to regulate growth, development, and metabolic rateIodized salt and seafood
IronStructural component of hemoglobin (which carries oxygen in the blood) and myoglobin (which makes oxygen available for muscle contraction) and other enzymes; necessary for the utilization of energyRed meats, fish, poultry, shellfish, legumes, dried fruits
MagnesiumOne of the factors involved in bone mineralization; maintain electrical potential in nerves and muscle membranes; involved in building of proteins, enzyme action, normal muscular contraction, transmission of nerve impulses, and maintenanceance of teethWidely distributed in most foods with nuts, fruits, vegetables, and cereals as best sources
ManganeseCofactor for enzymesWhole grains, leafy green vegetables, and wheat germ
MolybdenumXanthine oxidase, aldehyde oxidaseLegumes, whole grains, and wheat
PhosphorusBone and teeth formation; regulation of acid-base balance; present in cell’s genetic material as phospholipids, in energy transfer, and in buffering systemsMilk, poultry, fish, meat, and carbonated beverages
PotassiumRegulation of osmotic pressure and acid-base balance; activation of a number of intracellular enzymes; nerve and muscle contractionAll whole foods; meats, milk, fruits, vegetables, grains, and legumes
SeleniumPart of glutathione peroxidase (an enzyme that breaks down reactive chemicals that harm cells); works with vitamin ESeafood, organ meats, muscle meats, grains, and vegetables depending on soil conditions
SodiumRegulation of pH, osmotic pressure, and water balance; conductivity or excitability of nerves and muscles; active transport of glucose and amino acidsSalt, soy sauce, seafood, dairy products, and processed foods
ZincPart of the hormone insulin and many enzymes; taste perception; wound healing; metabolism of nucleic acidsRed meat; seafood, especially oysters; and beans