| Element | Source in human diet | Major functions |
|---|
| MACRONUTRIENTS | | |
| Calcium (Ca) | Dairy foods, eggs, green leafy vegetables, whole grains, legumes, nuts, meat | Found in bones and teeth; blood clotting; nerve and muscle action; enzyme activation |
| Chlorine (Cl) | Table salt (NaCl), meat, eggs, vegetables, dairy foods | Water balance; digestion (as HCl); principal negative ion in extracellular fluid |
| Magnesium (Mg) | Green vegetables, meat, whole grains, nuts, milk, legumes | Required by many enzymes; found in bones and teeth |
| Phosphorus (P) | Dairy, eggs, meat, whole grains, legumes, nuts | Component of nucleic acids, ATP, and phospholipids; bone formation; buffers; metabolism of sugars |
| Potassium (K) | Meat, whole grains, fruits, vegetables | Nerve and muscle action; protein synthesis; principal positive ion in cells |
| Sodium (Na) | Table salt, dairy foods, meat, eggs | Nerve and muscle action; water balance; principal positive ion in extracellular fluid |
| Sulfur (S) | Meat, eggs, dairy foods, nuts, legumes | Found in proteins and coenzymes; detoxification of harmful substances |
| MICRONUTRIENTS | | |
| Chromium (Cr) | Meat, dairy, whole grains, legumes, yeast | Glucose metabolism |
| Cobalt (Co) | Meat, tap water | Found in vitamin B12; formation of red blood cells |
| Copper (Cu) | Liver, meat, fish, shellfish, legumes, whole grains, nuts | Found in active site of many redox enzymes and electron carriers; production of hemoglobin; bone formation |
| Fluorine (F) | Most municipal water supplies | Found in teeth; helps prevent tooth decay |
| Iodine (I) | Fish, shellfish, iodized salt | Found in thyroid hormones |
| Iron (Fe) | Liver, meat, green vegetables, eggs, whole grains, legumes, nuts | Found in active sites of many redox enzymes and electron carriers, hemoglobin, and myoglobin |
| Manganese (Mn) | Organ meats, whole grains, legumes, nuts, tea, coffee | Activates many enzymes |
| Molybdenum (Mo) | Organ meats, dairy, whole grains, green vegetables, legumes | Found in some enzymes |
| Selenium (Se) | Meat, seafood, whole grains, eggs, milk, garlic | Fat metabolism |
| Zinc (Zn) | Liver, fish, shellfish, and many other foods | Found in some enzymes and some transcription factors; insulin physiology |