The major minerals that are essential for human beings include the following:

• Calcium. The most common mineral in the body, people obtain it from their diet. It is crucial to building and maintaining strong bones and teeth. In addition, calcium is involved in many other body processes, including maintaining fluid balance, muscle and blood vessel contraction, regulating the heartbeat and conducting nerve impulses to send messages through the nervous system. Calcium is also needed for proper blood clotting.
  
  
• Magnesium. Present in tiny amounts in the body. It has many different roles, including helping to make bone and other tissues, converting food to energy, and aiding in the activity of more than 300 enzymes (chemicals that regulate various bodily functions).
  
  
• Phosphorus. Like calcium, phosphorus is obtained from the diet and is essential for strong bones and teeth. It also helps transmit the genetic code of genes and chromosomes from cell to cell during cell division and growth. Phosphorus is part of the protective sheath around nerve cells (myelin sheath). Other tasks performed by this mineral include metabolizing carbohydrates and maintenance of the body’s pH balance.
  
  
• Sulfur. A mineral that is an integral component of all proteins. Sulfur is involved primarily in protein and certain enzyme synthesis. People who consume adequate levels of protein also get adequate levels of sulfur.

Three of the major minerals are also known collectively as the principal electrolytes. They work together to regulate the flow of fluids into and out of the body’s cells. They also transmit nerve impulses. The three electrolytes are:

• Chloride. A compound made up of the poisonous gas chlorine and sodium or hydrogen. This combination results in a nutrient required by the body. It is the major anion (negatively charged ion) contained mainly in the fluid outside body cells. Chloride helps the body maintain a normal balance of fluids.
  
  
• Potassium. Found in all living cells, including those of plants and animals. It is an essential part of electrical and cellular functions within the body and has various roles in metabolism. The digestive system, heart, kidneys, muscles and nerves all require potassium to function properly.
  
  
• Sodium. Occurs naturally in food and helps regulate the fluid balance of cells and plasma (the fluid portion of blood). Salt regulates both blood pressure and blood volume. Too little sodium in the body can result in dehydration because the cells are unable to retain water. Proper fluid balance is important to nutrition because it helps move nutrients into the cells and carries waste products out of the cells.

Trace minerals are present in the body in tiny amounts. They include:

• Chromium. Boosts the activity of the hormone insulin and appears to play a direct role in carbohydrate, fat and protein metabolism. It is found in certain enzymes in the body. Without adequate amounts of chromium, blood sugar levels may rise and a person may develop a diabetes-like condition.
  
  
• Copper. Found in all body tissues, it plays several vital roles in the body. It is necessary for the body’s absorption and use of the mineral iron. It is an antioxidant and helps deactivate free radicals, which are chemicals that bind together to damage body cells. Copper also helps the body create collagen and heal wounds, and is essential to many of the metabolic reactions that release energy for bodily processes.
  
  
• Fluoride. Component of the mineral fluorine that is naturally present in soil, water, air and certain foods (e.g., meat, fish, eggs, tea leaves). When fluoride enters the body, it is deposited into the teeth and bones, strengthening teeth during a process called remineralization (the rebuilding of tooth enamel). It is commonly added to community drinking water, and may be added to various foods and beverages during processing.
  
  
• Iodine. Plays a key role in the metabolism activity of cells and growth of tissues. It is part of the thyroid hormones thyroxin and triiodothyronine, which perform various roles in the body.
  
  
• Iron. Found in many foods, it is essential for good health. Iron helps red blood cells to carry oxygen throughout the body. However, many people experience iron deficiency, which may cause fatigue, weakness and other health problems. People with certain health conditions may be at risk of consuming too much iron, leading to iron overload, which may be toxic.
  
  
• Manganese. Essential component of enzymes that metabolize carbohydrates and fats. It is vital to maintaining a healthy immune system. In addition, pregnant women who consume manganese help to support the proper growth of fetal tissue such as bones and cartilage.
  
  
• Molybdenum. Part of several enzymes that metabolize proteins. It is mostly found in beans and grains, but may also appear in dairy products and drinking water.
  
  
• Selenium. Boosts the performance of enzymes, which help the body carry out many chemical reactions that are crucial for brain and body functions. It is required for the body to function normally, but only in small amounts.
  
  
• Zinc. Promotes cell division and growth, boosts the immune system and is involved in the repair of body tissues. It is necessary for normal growth and development during childhood, adolescence and during pregnancy. It also is important in boosting male fertility.