EDITORIAL & OPINION — Minerals essential to physical well-being — Prescription for healthier lives

“Mine-free by ’93” was one of many anti-mining slogans adopted by environmental extremists in the late 1980s as they tried to convince the public that there was no longer a need to extract metals and minerals from the earth’s crust. Fortunately, people didn’t exactly take to the notion of living au naturel in unheated caves in some remote wilderness preserve.

While many appreciate the benefits of civilization and realize that mining is essential to modern life, few among us realize how essential minerals and metals are to human health. Some extremists perpetuate the myth that naturally occurring metals in soils and water are contaminants, when in fact they may be life-savers.

In humans, the essential trace elements (or “inorganic micronutrients,” as they are now commonly called) are iron, zinc, copper, selenium, manganese, molybdenum, chromium and iodine. Scientists also believe that other elements, such as boron, silicon, and possibly even cadmium, nickel, arsenic and tin, may also be essential.

It wasn’t long ago that many North Americans suffered from iron and iodine deficiencies, which affected neurological development and, therefore, were of considerable socio-economic importance. While these deficiencies have been virtually eradicated in developed countries, scientists estimate that 600 million people in under-developed countries still suffer from iron deficiency and 200 million from iodine deficiency.

Various international programs have been established to eliminate these problems, which usually show up in infants, children and pregnant women. Great success has been noted with iodine supplementation, and selenium supplementation is reported to have virtually eliminated a particular form of fatal heart disease that occurred extensively in China.

In Europe and North America, leading cancer researchers have launched a multi-national prevention trial that calls for a definitive test of the hypothesis that supplements of the essential trace mineral selenium can prevent several types of cancers in humans.

This $40-million trial is expected to involve 52,000 participants in six countries. It is being led by doctors at the University of Arizona Cancer Center, whose earlier cancer prevention trial in the U.S. observed a 47% reduction in the incidence of cancer and a 50% reduction in cancer mortality in individuals receiving a supplement of selenium.

Selenium also is being investigated as a protective substance against other health problems, including heart disease. This essential nutrient is supplied naturally in human diet by both animal and plant food products, which obtain it from the soil. However, there are extensive areas in the U.S. and other countries where soil selenium is deficient. Most of the selenium that is used to remedy deficiencies in these areas is produced commercially as a byproduct of the refining of copper ores.

Humans also benefit from essential micronutrients of iron, zinc and copper. Mild deficiencies of zinc stunt growth and, to some degree, maturation in children, particularly boys. Zinc and copper supplements have been found to be useful in treating children suffering from malnutrition. Even cobalt is essential, though only in the organic form in Vitamin B12.

We realize, of course, that heavy concentrations of metals in soils and water are harmful to human health and eco-systems. Scientists also warn that multi-element supplementation programs have risks, as the properties of the various micronutrients can interfere with each other’s absorption and possibly induce further deficiencies. Another problem is that scientists have not yet determined how much of these micronutrients are required to maintain good health. While much research remains to be done, studying the relationship between metals and minerals and human health offers huge potential benefits to society.