Minerals

• CalciumThe most abundant mineral in the body. Almost all of it is stored in bones and teeth, and the gut needs vitamin D to absorb it.
• ChlorideThe partner of sodium in salt, needed for fluid balance and stomach acid. Its official values date from 2005 and were set to match sodium's, molecule for molecule.
• ChromiumA trace mineral that may enhance insulin's action. Its official intake dates from 2001, and whether it is essential at all is now disputed.
• CopperA mineral that enzymes for energy production, iron metabolism, connective tissue and brain chemicals depend on. Shellfish, organ meats, nuts, seeds and chocolate are rich sources.
• FluorideThe form of fluorine that protects teeth against decay. Most Americans get it from fluoridated tap water, toothpaste and food and drinks made with that water.
• IodineA trace mineral the thyroid needs to make its hormones, which control metabolism and are essential for brain and bone development before birth and in infancy.
• IronA mineral the body needs to make hemoglobin, which carries oxygen in the blood. Women aged 19 to 50 need more than twice as much as men.
• MagnesiumA mineral that more than 300 enzyme systems depend on — for muscle and nerve function, blood sugar and blood pressure control, energy production and bone.
• ManganeseA trace mineral many enzymes need, for metabolism, bone formation, reproduction and immune response. Whole grains, shellfish, nuts and tea are good sources.
• MolybdenumA trace mineral four enzymes need to break down sulfur-containing amino acids, purines and some drugs and toxins. Legumes are the richest sources.
• PhosphorusA mineral in bones, teeth, DNA and ATP, the body's energy currency. Most Americans get more than they need, partly from phosphate additives in processed food.
• PotassiumA mineral every cell needs for nerve signals, muscle contraction and kidney function, closely linked with sodium. Most Americans get less than recommended.
• SeleniumA mineral built into 25 proteins that matter for thyroid hormones, DNA synthesis, reproduction and protection from oxidative damage. Brazil nuts are exceptionally rich in it.
• SodiumThe main mineral in the fluid outside cells, eaten mostly as salt. Most U.S. adults eat more than the level above which cutting back is expected to lower the risk of heart disease.
• ZincA mineral that hundreds of enzymes need, involved in immune function, protein and DNA synthesis, wound healing and the sense of taste. Oysters and beef are rich sources.