In the context of nutrition, a mineral
is a chemical element required as an essential nutrient by organisms to perform
functions necessary for life. Minerals originate in the earth and cannot be made by living
organisms. Plants get minerals from soil. Most of the minerals in a
human diet come from eating plants and animals or from drinking water. As a
group, minerals are one of the four groups of essential nutrients, the
others of which are vitamins, essential fatty acids, and essential amino acids.
The five major minerals in the human body are calcium, phosphorus, potassium, sodium, and magnesium. All of the remaining elements in a human body are called "trace elements". The trace elements that have a specific biochemical function in the human body are sulfur, iron, chlorine, cobalt, copper, zinc, manganese, molybdenum, iodine and selenium.
Most chemical elements that are ingested by organisms are in the form of simple compounds. Plants absorb dissolved elements in soils, which are subsequently ingested by the herbivores and omnivores that eat them, and the elements move up the food chain. Larger organisms may also consume soil (geophagia) or use mineral resources, such as salt licks, to obtain limited minerals unavailable through other dietary sources.
Bacteria and fungi play an essential role in the weathering of primary elements that results in the release of nutrients for their own nutrition and for the nutrition of other species in the ecological food chain. One element, cobalt, is available for use by animals only after having been processed into complex molecules (e.g., vitamin B12) by bacteria. Minerals are used by animals and microorganisms for the process of mineralizing structures, called "biomineralization", used to construct bones, seashells, eggshells, exoskeletons and mollusc shells.
At least twenty chemical elements are known to be required to support human biochemical processes by serving structural and functional roles as well as electrolytes. However, as many as twenty-nine elements in total (including hydrogen, carbon, nitrogen and oxygen) are suggested to be used by mammals, as inferred by biochemical and uptake studies. Calcium makes up 920 to 1200 mg of adult body weight, with 99% of it contained in bones and teeth. Phosphorus makes up about 1% of a person's body weight. The other major minerals (potassium, sodium, chlorine, sulfur and magnesium) make up only about 0.85% of the weight of the body. Together these eleven chemical elements (H, C, N, O, Ca, P, K, Na, Cl, S, Mg) make up 99.85% of the body.
Most of the known and suggested mineral nutrients are of relatively low atomic weight, and are reasonably common on land, or, at least, common in the ocean (iodine, sodium).
The five major minerals in the human body are calcium, phosphorus, potassium, sodium, and magnesium. All of the remaining elements in a human body are called "trace elements". The trace elements that have a specific biochemical function in the human body are sulfur, iron, chlorine, cobalt, copper, zinc, manganese, molybdenum, iodine and selenium.
Most chemical elements that are ingested by organisms are in the form of simple compounds. Plants absorb dissolved elements in soils, which are subsequently ingested by the herbivores and omnivores that eat them, and the elements move up the food chain. Larger organisms may also consume soil (geophagia) or use mineral resources, such as salt licks, to obtain limited minerals unavailable through other dietary sources.
Bacteria and fungi play an essential role in the weathering of primary elements that results in the release of nutrients for their own nutrition and for the nutrition of other species in the ecological food chain. One element, cobalt, is available for use by animals only after having been processed into complex molecules (e.g., vitamin B12) by bacteria. Minerals are used by animals and microorganisms for the process of mineralizing structures, called "biomineralization", used to construct bones, seashells, eggshells, exoskeletons and mollusc shells.
Essential Chemical Elements
for Humans
At least twenty chemical elements are known to be required to support human biochemical processes by serving structural and functional roles as well as electrolytes. However, as many as twenty-nine elements in total (including hydrogen, carbon, nitrogen and oxygen) are suggested to be used by mammals, as inferred by biochemical and uptake studies. Calcium makes up 920 to 1200 mg of adult body weight, with 99% of it contained in bones and teeth. Phosphorus makes up about 1% of a person's body weight. The other major minerals (potassium, sodium, chlorine, sulfur and magnesium) make up only about 0.85% of the weight of the body. Together these eleven chemical elements (H, C, N, O, Ca, P, K, Na, Cl, S, Mg) make up 99.85% of the body.
Most of the known and suggested mineral nutrients are of relatively low atomic weight, and are reasonably common on land, or, at least, common in the ocean (iodine, sodium).
Elements Considered Possibly
Essential but not Confirmed
Many ultratrace
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. Ultratrace elements of some minerals such as silicon
and boron are known to have a role but the exact biochemical nature is unknown,
and others such as arsenic and chromium are suspected to have a role in health,
but with weaker evidence. Chromium is considered and essential mineral by the
U.S. Institute of Medicine but not for the European Food Safety Authority,
which makes the decisions for the European Union. Roles for trace minerals
include enzyme catalysis, attracting substrate molecules, redox reactions, and
structural or regulatory effects on protein binding.
These elements
include bromine, arsenic, nickel, fluorine, boron, lithium,
strontium, possibly silicon and vanadium and potentially possibly aluminum, germanium, lead, rubidium, and tin.
Footnote by the Blog Author
The text linked
above also notes that “tungsten, lanthanum,
and cadmium have specialized biochemical uses
in certain lower organisms, but these elements appear not to be utilized by
humans.” Silver has antibacterial
properties and gold interrupts chemical processes of rheumatoid arthritis. Silver and gold have the same valence as copper and may be able
to substitute for certain functions performed by copper.
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