By definition, essential minerals are substances that cannot be manufactured by the body but are required to execute various biological processes. That sounds straightforward, yet the term "mineral" is misleading because it implies that it is a crystalline chemical compound produced by a geological event, when it's actually a pure, inorganic chemical element. To add to the confusion, experts differ on exactly how many minerals are considered essential.
According to MedlinePlus, essential minerals are divided into two classifications: macrominerals and trace minerals. The body requires macrominerals in significant amounts for optimum functioning. MedlinePlus lists calcium, phosphorus, magnesium, sodium, potassium, chloride and sulfur among essential macrominerals. In contrast, only small amounts of trace minerals are needed. Trace minerals include cobalt, copper, fluoride, iodine, iron, manganese, selenium and zinc.
Minerals Considered Essential
While most nutritional authorities agree that there are seven major or macrominerals, there are differences of opinion as to the number of trace minerals that are considered essential. For instance, in a pamphlet titled, “The Benefits of Nutritional Supplements” written for the Council of Responsible Nutrition, author Annette Dickinson, Ph.D., includes molybdenum as an essential trace mineral. However, MedlinePlus does not. Going by Dr. Dickinson's account, this would place the total number of minerals considered to be essential at 16.
Some of the major essential minerals, namely calcium, potassium and zinc, are used by the body to digest food, produce energy and regulate cholesterol. Calcium, magnesium and phosphorus are essential for health teeth, bones and connective tissue. According to The National Health Museum, 11 trace minerals are essential for growth and development because they are involved in oxygen transport and various metabolic functions, and serve as catalysts for enzymatic reactions.
Because many minerals are essential for good health, mineral deficiencies can lead to disease. The National Health Museum states that the most common mineral deficiencies involve iron and calcium, resulting in anemia and impaired bone density, respectively. According to Dr. Dickinson, selenium is needed to manufacture glutathione perixidase, a lack of which may lead to oxidative stress and an increased risk of heart disease. A deficiency in chromium may impair glucose uptake and utilization. As with calcium, an insufficient intake of copper may result in bone loss.
Expert committees, such as the National Academy of Sciences, the Institute of Medicine and the Food and Nutrition Board, determine dietary recommendations for essential minerals and other nutrients. You are probably familiar with the standard RDA, or recommended daily allowance guidelines. However, according to Dr. Dickinson, dietary recommendations are now given as DRIs, or dietary reference intakes. DRIs incorporate several parameters in addition to RDA, including estimated average requirement, or EAR; adequate intake, or AI; and upper level of tolerable intake, or UL.