Mineral

Good Sources

Main Functions

Recommended Dietary Allowance for adults

Safe Upper Limit

Calcium

Milk and milk products, meat, fish, eggs, cereal products, beans, fruits, and vegetables

Required for the formation of bone and teeth, for blood clotting, for normal muscle function, and for normal heart rhythm

1,000 milligrams

1,200 milligrams for people older than 50

2,500 milligrams

Chloride

Salt, beef, pork, sardines, cheese, green olives, corn bread, potato chips, sauerkraut, and processed or canned foods

Involved in electrolyte balance

1,000 milligrams

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Copper

Organ meats, shellfish (especially oysters), chocolate, mushrooms, nuts, dried legumes, and whole-grain cereals

Used to form enzymes that are necessary for energy production, for antioxidation (protection against cell damage due to reactive by-products of normal cell activity called free radicals), and for formation of the hormone epinephrine, red blood cells, bone, and connective tissue

900 micrograms

10,000 micrograms

Fluoride

Saltwater fish, tea, coffee, and fluoridated water

Required for the formation of bone and teeth

3 milligrams for women

4 milligrams for men

10 milligrams

Iodine

Seafood, iodized salt, dairy products, and drinking water (in amounts that vary by the iodine content of local soil)

Required for the formation of thyroid hormones

150 micrograms

1,100 micrograms

Iron

As heme iron:

Meats, poultry, fish, kidneys, and liver

As nonheme iron: Soybean flour, beans, molasses, spinach, clams, dried fruit, and fortified cereals

Required for the formation of many enzymes in the body

Is an important component of muscle cells and of hemoglobin (which enables red blood cells to carry oxygen and deliver it to the body's tissues)

8 milligrams

18 milligrams for women younger than 50 (premenopause)

27 milligrams for pregnant women

9 milligrams for breastfeeding women

45 milligrams

Magnesium

Leafy green vegetables, nuts, cereal grains, and seafood

Required for the formation of bone and teeth, for normal nerve and muscle function, and for the activation of enzymes

320 milligrams for women

420 milligrams for men

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Phosphorus

Milk, cheese, meat, poultry, fish, cereals, nuts, and legumes

Required for the formation of bone and teeth and for energy production

Used to form nucleic acids, including DNA (deoxyribonucleic acid)

700 milligrams

4,000 milligrams

Potassium

Whole and skim milk, bananas, tomatoes, oranges, melons, potatoes, sweet potatoes, prunes, raisins, spinach, turnip greens, collard greens, kale, other green leafy vegetables, most peas and beans, and salt substitutes (potassium chloride)

Required for normal nerve and muscle function

Involved in electrolyte balance

3.5 grams

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Selenium

Meats, seafood, and cereals (depending on the selenium content of soil where grains were grown)

Acts as an antioxidant, with vitamin E, protecting cells against damage by free radicals, which are reactive by-products of normal cell activity

Required for thyroid gland function

55 micrograms

400 micrograms

Sodium

Salt, beef, pork, sardines, cheese, green olives, corn bread, potato chips, sauerkraut, and processed or canned foods

Required for normal nerve and muscle function

Involved in electrolyte balance

1,000 milligrams

2,400 milligrams

Zinc

Organ meats such as liver, eggs, and seafood

Used to form many enzymes and insulin

 

Required for healthy skin, healing of wounds, and growth

15 milligrams

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