Other Elements
Many elements have been suggested as essential, but such claims have usually not been confirmed. Definitive evidence for efficacy comes from the characterization of a biomolecule containing the element with an identifiable and testable function. One problem with identifying efficacy is that some elements are innocuous at low concentrations and are pervasive (examples: silicon and nickel in solid and dust), so proof of efficacy is lacking because deficiencies are difficult to reproduce.
| Element | Description | Excess |
|---|---|---|
| Sulfur | Relatively large quantities of sulfur are required, but there is no RDA, as the sulfur is obtained from and used for amino acids, and therefore should be adequate in any diet containing enough protein. | (primarily associated with compounds) |
| Cobalt | Cobalt is required in the synthesis of vitamin B12, but because bacteria are required to synthesize the vitamin, it is usually considered part of vitamin B12 deficiency rather than its own dietary element deficiency. | Cobalt poisoning |
| Nickel | There have been occasional studies asserting the essentiality of nickel, but it currently has no RDA. | Nickel toxicity |
| Chromium | Chromium has been described as nonessential to mammals. Some role in sugar metabolism in humans has been invoked, but evidence is lacking, despite a market for the supplement chromium picolinate. | Chromium toxicity |
| Fluorine | Fluorine (as Fluoride) is not generally considered an essential mineral element because humans do not require it for growth or to sustain life. However, if one considers the prevention of dental cavities an important criterion in determining essentiality, then fluoride might well be considered an essential trace element. However, recent research indicates that the primary action of fluoride occurs topically (at the surface). | Fluoride poisoning |
| Boron | Boron has been found to be essential for the utilization of vitamin D and calcium in the body. | |
| Strontium | Strontium has been found to be involved in the utilization of calcium in the body. It has promoting action on calcium uptake into bone at moderate dietary strontium levels, but a rachitogenic (rickets-producing) action at higher dietary levels. | Rachitogenic |
| Other | Arsenic, silicon, and vanadium have established, albeit specialized, biochemical roles as structural or functional cofactors in other organisms, and are possibly, even probably, used by mammals (including humans). By contrast, tungsten, bromine, and cadmium have specialized biochemical uses in certain lower organisms, but these elements appear not to be utilized by humans. | Multiple |
Read more about this topic: Dietary Mineral
Famous quotes containing the word elements:
“In spite of all their kind some elements of worth
With difficulty persist here and there on earth.”
—Hugh MacDiarmid (1892–1978)
“It is a life-and-death conflict between all those grand, universal, man-respecting principles which we call by the comprehensive term democracy, and all those partial, person-respecting, class-favoring elements which we group together under that silver-slippered word aristocracy. If this war does not mean that, it means nothing.”
—Antoinette Brown Blackwell (1825–1921)