8 important trace minerals

A varied and balanced diet provides all the essential minerals you need. Only trace amounts of some minerals are required. Here are eight important trace minerals that should be included in your diet.

Insulin and chromium appear to act together to metabolize glucose, the body's major fuel.

• Brewer's yeast is high in chromium; other sources include wheat germ, whole-grain products, liver, cheese, chicken, mushrooms, peas and molasses.

Copper is essential for making red blood cells, skin pigment, connective tissue and nerve fibres; it also stimulates absorption of iron.

• Copper deficiency results in anemia, deterioration of the heart muscle, inelastic blood vessels, various skeletal defects and more. Liver is the richest source of copper.
• Using unlined copper pans can result in copper toxicity.
• Excessive copper can cause severe liver disease and mental deterioration.

This mineral is necessary to make thyroid hormones.

• An iodine deficiency can result in an overgrown thyroid gland, or goiter; in severe cases, it can lead to hypothyroidism. In addition, a baby borne by a woman with iodine deficiency may develop cretinism, a devastating type of mental retardation.
• Seafood, kelp and vegetables grown in iodine-rich soil are good sources of the mineral.
• Iodized salt is advisable in areas where the soil lacks iodine.

75 percent of the body's iron is in hemoglobin, the pigment in red blood cells that carries oxygen.

• Iron-deficiency anemia is the most common nutritional deficiency in developed countries.
• Consuming nonheme iron with vitamin C or meat increases its absorption.
• People most likely to develop an iron deficiency are teenagers, menstruating women, pregnant women, preschool children, some athletes and people on very restricted diets.

An important antioxidant, selenium interacts with vitamin E to prevent the free radicals produced during oxygen metabolism from damaging body fat and other tissues.

• Research is looking at the role of selenium in lowering risk of lung, prostate, stomach and colorectal cancers.
• Foods high in selenium include Brazil nuts, seafood, some meats and fish, whole-grain products, oats and brown rice.

Zinc is necessary for some metabolic processes, normal growth and sexual development and proper immune system function. It's also needed to make genetic materials and for proper wound healing.

• Deficiencies result in increased susceptibility to infection, fatigue, appetite loss, balding and taste abnormalities.
• Zinc is found in many foods; good sources include beef and other meats, oysters and other seafood, eggs, milk, yogurt, wheat germ and nuts.
• The phytates in whole-grain products and other plant products, however, bind with zinc and prevent absorption. For this reason, vegetarians may need much more zinc than non-vegetarians.

Along with sodium, potassium helps regulate the body's balance of fluids. Potassium is instrumental in the transmission of nerve impulses, proper muscle function and maintaining normal blood pressure.

• Most plant foods contribute varying amounts of potassium; rich sources include dried fruits, bananas, tomatoes, citrus fruits, avocados, potatoes, milk and melons.

Sodium is largely responsible for determining the body's total water content. Like potassium, sodium ions help regulate nerves and muscles. These two electrolytes maintain the fluid balance inside and outside of body cells. Sodium maintains the acid-base balance, sends nerve impulses and helps muscle contraction.

• Excessive salt is linked to high blood pressure; it can also cause swollen ankles and fingers and other signs of a buildup of body fluids.

These trace minerals have an important role and contribute to your overall health. Keep this guide in mind and avoid mineral deficiencies by eating foods that offer these trace minerals.