There are 92 elements that are found in nature with 22 other documented or theoretical elements. In sea water, there are approximately 66 elements that have been identified to date. Each year, as more research is conducted and the results disseminated among health professionals, the media and consumers, minerals and trace minerals are garnering more recognition and consideration for the beneficial role they play in human health. During the next few years, there will continue to be an expansion or "golden-age" of knowledge concerning the essential role of a number of minerals and trace minerals in health and nutrition.

Listed below, in this section, are identified elements that have been studied for their role in nutrition.

Aluminum
The average daily intake varies between 3 to 100 mg. Sources of aluminum (Al) include baked goods prepared with leavening agents, i.e. baking powder, processed cheese, grains, vegetables, certain antacids, white flour, etc.1,2 There is no established function of aluminum in human health.2 Al, if consumed in high amounts, can be fatal.2 However according to Nutrition Almanac, Adelle Davis, author, speaker and pioneer of America's "Health Food" movement, reported that magnesium can displace aluminum in the body. A patient of Davis' suffering from irritability, poor concentration and memory due to aluminum toxicity was able to end the symptoms after taking magnesium supplements.2


Arsenic
Although arsenic (As) is well-known for its toxic properties, it has been shown to be beneficial when fed to animals in small amounts. Numerous animals studies involving rats, hamsters, goats and chicks has provided circumstantial evidence that arsenic is essential. In goats, as deficiency resulted in decreased growth rates, impaired fertility and increased infant mortality.3 Based on animals studies then extrapolated to humans, the dietary intake of As is equal to 12.5-25 mcg/day.1 Human diets normally contain 12-50 mcg/day. Nutritionists advise a safe upper intake of arsenic could well be 140-250 mcg/day.4


Beryllium
This mineral is a component of many industrial processes including electronic devices and some alloys such as steel, bicycle wheels and other household products. Estimated intakes of this element approximately 100 mcg/day.5 In industrial toxicology, inhalation of beryllium (Be) dust has led to lung injury, scarring or fibrosis.2 However, the literature does not report a case of beryllium toxicity associated with a dietary supplement that contains trace amounts of Be.5 Some studies have shown that 1 ppm of beryllium chloride prevents calcification of the precursor that is associated with increased risk of dental caries.5


Bismuth
Bismuth (Bi) has no known function within the body. Bi has been used historically to treat syphilis and today, is an ingredient in certain antidiarrhoea medications and rectal suppositories. Bi toxicity can cause staggering gait, poor memory, tremors and visual and hearing disturbances.2


Bromine
The typical daily intake of bromine (Br) is 2 to 8 mg. Br is normally ingested as the bromide ion, which has a low degree of toxicity, and, as such, does not pose a toxicological threat in terms of nutrition. Some studies suggest Br may be nutritionally beneficial (i.e., low Br levels associated with hemodialysis patients with insomnia).1


Cadmium
The typical dietary intake of this element daily is 10-20 mcg.1 Cadmium (Cd), found in cigarette smoke, industrialisation, and population growth has a long half life (10-30 yrs.) and high intakes can cause organ damage, especially kidney damage. If there is a deficiency of zinc in the diet, the body will compensate, storing cadmium.2 Cd is known to experimentally cause hypertension, cancer and immune disorders. In prostate cancer, there is a correlation between the grade of malignancy and cadmium content.5 However, little cadmium is absorbed orally unless there are nutrient deficiencies. Other elements and nutrients that confer a protective effect against cadmium include: zinc, calcium, vitamin C and sulphur amino acids.5


Germanium
Typical daily intakes hover between 0.4-1.5 mg. The maximum safe intake level of germanium (Ge) should be >30 mg per day or 0.43 mg/kg/d for a healthy adults and >7.5 mg per day in a healthy child, says Alexander Schauss.5 Some organic forms of germanium are less toxic than inorganic forms. Inorganic germanium toxicity can result in damage to the kidneys. There have been reports of kidney failure with organic germanium supplements, however, the intake ranged from 16-328 grams over a 4-36-month period.2,5 Germanium appears to improve cellular oxygenation, according to Prescription for Nutritional Healing.


Lead
Typical daily intakes are 15-100 mcg per day. In animal studies, lead (Pb) deficiency had adverse effects on growth and disturbed iron metabolism. Although beneficial in minute amounts, toxicity is more of a nutritional concern.1 Humans can only tolerate 1-2 mg of Pb without suffering toxic effects including anaemia, kidney damage, and central nervous system abnormalities.1,2


Mercury
The average daily intake of mercury is estimated to be only 0.5 mg.2 Mercury (Hg) has no known essential function in the body and is a toxic element presenting numerous hazards if it is ingested or inhaled. Individuals can be exposed to mercury through industrial processes, consuming fish or wild game contaminated with Hg as a result of industrial discharge and/or mercury-containing fillings. Two forms of mercury, methyl and phenyl mercury, deplete brain tissues of zinc.2


Nickel
An essential element for higher animals, a deficiency disease has not been identified for humans.6 Human requirement for nickel (Ni) probably does not exceed 100 mcg/day. Average intakes of Western-based diet ranges from 60-260 mcg/day. Ni, demonstrated through animal and human tests, plays a role in hormone and lipid and membrane metabolism.2 It can act as an activator of certain enzymes and may be involved in glucose metabolism.2 The oral toxic dose is about 1,000 times the amount consumed in food.

Nickel can be toxic to humans if intake levels are high. Excessive amounts of nickel in tissue can lead to altered hormone and enzyme activities and can impact glucose tolerance, blood pressure and immune function.6


Phosphorous
Needed for proper bone and tooth formation, cell growth and contraction of the heart muscle, phosphorous (P) also assists in the assimilation of vitamins and the conversion of food to energy.1 It also works with calcium to maintain the calcium-phosphorous balance in the bones of 2.5 parts calcium to 1 part P.2 The recommended amount in the USA is 800 mg/day for men and women. Deficiency can cause lack of appetite and weight loss. There is no known toxicity of phosphorous.


Rubidium
Typical daily intake of rubidium (Rb) is 1-5 mg. Rb is relatively non-toxic and does not pose toxicological concern. In animals, specifically goats, Rb deficiency depresses growth and life expectancy.1


Silicon
Found in the connective tissue of the body including the aorta, trachea, tendons, bone and skin, silicon (Si) also works with calcium to form strong bones, which has implications for osteoporosis.2,3 It also stimulates the immune system and inhibits the aging process in tissues.1 Aging increases the need for silicon. Recommended intakes range from 5-10mg/day.3


Strontium
There is evidence to suggest strontium (Sr) is an essential trace mineral.2 It is similar to calcium in chemical composition and is necessary for proper bone growth and prevention of dental caries.2 Researchers at St. Mary's Hospital in Montreal, Canada, have found that Sr may confer a protective effect of certain energy-producing structures within the cell. Not to be confused with radioactive strontium 90, Sr is stable and one of the least toxic trace elements.2


Sulphur
Sulphur (S) accounts for 0.25 % of human body weight.2 Referred to as nature's "beauty mineral," it works with other nutrients in protein and synthesis, which increase hair glossiness and smoothness and maintains a clear, youthful appearance.2 Sulphur also plays a role in bacteria resistance, bile secretion and the aging process.7 Sulphur is stored in each cell of the body with the highest amounts found in the joints, hair, skin and nails. 2There is no RDA for sulphur.


Tin
In 1960, tin (Sn) was designated as an essential trace element. Tin-deficiency in animals has resulted in poor growth and haemoglobin synthesis.2 Widely used in many industrial processes, a tin salt, stannous fluoride, is used in commercial toothpastes.2 Estimated daily intakes range from 2-17 mg/day. Estimated requirements hover between 3-4 mg/day.2


Vanadium
There is strong circumstantial evidence for the essentiality of vanadium (V). It is present in most body tissues. Cartilage, bones and teeth require vanadium for proper development. It also plays a role in growth and reproduction and cholesterol synthesis.7 Animal studies show that V deficiency in increased rates of spontaneous abortion, infant mortality, skeletal deformities.1,2,4 V is a component of many sports performance enchanters or advertised for its beneficial effects on glucose metabolism.4 High doses of vanadium, however, may be toxic to humans.3 In animal studies, V toxicity has adverse effects reduced blood glucose levels, diarrhoea, red blood cells and caused immunosuppression.5