Trace Minerals Information
Dietary minerals are the chemical elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen present in common organic molecules. The term "mineral" is archaic, since the intent of the definition is to describe chemical elements, not chemical compounds or actual minerals. Examples include calcium, magnesium, potassium, sodium, zinc, and iodine.
Dietitians may recommend that dietary elements are best supplied by ingesting specific foods rich with the chemical element(s) of interest. The elements may be naturally present in the food (e.g., calcium in dairy milk) or added to the food (e.g., orange juice fortified with calcium; iodized salt, salt fortified with iodine). Dietary supplements can be formulated to contain several different chemical elements (as compounds), a combination of vitamins and/or other chemical compounds, or a single element (as a compound or mixture of compounds), such as calcium (as carbonate, citrate, etc.) or magnesium (as oxide, etc.), chromium (usually as picolinate).
The dietary focus on chemical elements derives from an interest in supporting the biochemical reactions of metabolism with the required elemental components.[1] Appropriate intake levels of certain chemical elements have been demonstrated to be required to maintain optimal health. Diet can meet all the body's chemical element requirements, although supplements can be used when some requirements (e.g., calcium, which is found mainly in dairy products) are not adequately met by the diet, or when chronic or acute deficiencies arise from pathology, injury, etc.
Essential chemical elements
Some sources state that sixteen chemical elements are required to support human biochemical processes by serving structural and functional roles as well as electrolytes:[2] Most of the dietary elements are of relatively low atomic weight:
Periodic table highlighting dietary elements
| H |
|
He |
| Li |
Be |
|
B |
C |
N |
O |
F |
Ne |
| Na |
Mg |
|
Al |
Si |
P |
S |
Cl |
Ar |
| K |
Ca |
Sc |
|
Ti |
V |
Cr |
Mn |
Fe |
Co |
Ni |
Cu |
Zn |
Ga |
Ge |
As |
Se |
Br |
Kr |
| Rb |
Sr |
Y |
|
Zr |
Nb |
Mo |
Tc |
Ru |
Rh |
Pd |
Ag |
Cd |
In |
Sn |
Sb |
Te |
I |
Xe |
| Cs |
Ba |
La |
* |
Hf |
Ta |
W |
Re |
Os |
Ir |
Pt |
Au |
Hg |
Tl |
Pb |
Bi |
Po |
At |
Rn |
| Fr |
Ra |
Ac |
** |
Rf |
Db |
Sg |
Bh |
Hs |
Mt |
Ds |
Rg |
|
| |
| |
* |
Ce |
Pr |
Nd |
Pm |
Sm |
Eu |
Gd |
Tb |
Dy |
Ho |
Er |
Tm |
Yb |
Lu |
|
| |
** |
Th |
Pa |
U |
Np |
Pu |
Am |
Cm |
Bk |
Cf |
Es |
Fm |
Md |
No |
Lr |
|
| The four organic basic elements |
Quantity elements |
Essential trace elements |
Pervasive but no identified biological function in humans |
The following play important roles in biological processes:
| Dietary element |
RDA/AI |
Description |
Category |
Insufficiency |
Excess |
| Potassium |
4700 mg |
Quantity |
is a systemic electrolyte and is essential in coregulating ATP with sodium. Dietary sources include legumes, potato skin, tomatoes, and bananas. |
hypokalemia |
hyperkalemia |
| Chlorine |
2300 mg |
Quantity |
is needed for production of hydrochloric acid in the stomach and in cellular pump functions. Table salt (sodium chloride) is the main dietary source. |
hypochloremia |
hyperchloremia |
| Sodium |
1500 mg |
Quantity |
is a systemic electrolyte and is essential in coregulating ATP with potassium. Dietary sources include table salt (sodium chloride, the main source), sea vegetables, milk, and spinach. |
hyponatremia |
hypernatremia |
| Calcium |
1000 mg |
Quantity |
is needed for muscle, heart and digestive system health, builds bone, supports synthesis and function of blood cells. Dietary sources of calcium include dairy products, canned fish with bones (salmon, sardines), green leafy vegetables, nuts and seeds. |
hypocalcaemia |
hypercalcaemia |
| Phosphorus |
700 mg |
Quantity |
is a component of bones (see apatite), cells, in energy processing and many other functions.[3] In biological contexts, usually seen as phosphate.[4] |
hypophosphatemia |
hyperphosphatemia |
| Magnesium |
420 mg |
Quantity |
is required for processing ATP and for bones. Dietary sources include nuts, soy beans, and cocoa mass. |
hypomagnesemia,
magnesium deficiency |
hypermagnesemia |
| Zinc |
11 mg |
Trace |
is pervasive and required for several enzymes such as carboxypeptidase, liver alcohol dehydrogenase, and carbonic anhydrase. |
zinc deficiency |
zinc toxicity |
| Iron |
8 mg |
Trace |
is required for many proteins and enzymes, notably hemoglobin to prevent anemia. Dietary sources include red meat, leafy green vegetables, fish (tuna, salmon), eggs, dried fruits, beans, whole grains, and enriched grains. |
anaemia |
iron overload disorder |
| Manganese |
2.3 mg |
Trace |
is a cofactor in enzyme functions. |
manganese deficiency |
manganism |
| Copper |
900 µg |
Trace |
is required component of many redox enzymes, including cytochrome c oxidase. |
copper deficiency |
copper toxicity |
| Iodine |
150 µg |
Trace |
is required not only for the synthesis of thyroid hormones, thyroxine and triiodothyronine and to prevent goiter, but also, probably as an antioxidant, for extrathyroidal organs as mammary and salivary glands and for gastric mucosa and immune system (thymus):
|
iodine deficiency |
iodism |
| Selenium |
55 µg |
Trace |
a cofactor essential to activity of antioxidant enzymes like glutathione peroxidase. |
selenium deficiency |
selenosis |
| Molybdenum |
45 µg |
Trace |
the oxidases xanthine oxidase, aldehyde oxidase, and sulfite oxidase[5] |
molybdenum deficiency |
|
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, so proof of efficacy is lacking because deficiencies are difficult to reproduce.[1]
| Element |
Description |
Excess |
| Sulfur |
Relatively large quantities of sulfur are required, but there is no RDA,[6] 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,[7] but it currently has no known RDA. |
Nickel toxicity |
| Chromium |
Chromium is sometimes described as essential.[8][9] It is implicated in sugar metabolism in humans, leading to a market for the supplement chromium picolinate, but definitive biochemical evidence for a physiological function is lacking.[10] |
Chromium toxicity |
| Fluorine |
Fluorine (as fluoride) has been described as conditionally essential, depending upon the importance placed upon the prevention of chronic disease.[11][12] |
Fluoride poisoning |
| Boron |
Boron has been found to be essential for the utilization of vitamin D and calcium in the body.[13] |
|
| 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 the rachitogenic action at higher dietary levels.[14] |
Rachitogenic |
| Other |
Arsenic, bromine, cadmium, silicon, tungsten, and vanadium have established, albeit specialized, biochemical roles as structural or functional cofactors in other organisms. These elements appear not to be utilized by humans.[citation needed] |
Multiple |
See also
External links
References
- ^ a b Lippard, Stephen J.; Jeremy M. Berg (1994). Principles of Bioinorganic Chemistry. Mill Valley, CA: University Science Books. pp. 411. ISBN 0935702725.
- ^ Nelson, David L.; Michael M. Cox (2000-02-15). Lehninger Principles of Biochemistry, Third Edition (3 Har/Com ed.). W. H. Freeman. pp. 1200. ISBN 1572599316.
- ^ Corbridge, D. E. C. (1995-02-01). Phosphorus: An Outline of Its Chemistry, Biochemistry, and Technology (5th ed.). Amsterdam: Elsevier Science Pub Co. pp. 1220. ISBN 0444893075.
- ^ "Linus Pauling Institute at Oregon State University". http://lpi.oregonstate.edu/infocenter/minerals/phosphorus/. Retrieved 2008-11-29.
- ^ Sardesai VM (December 1993). "Molybdenum: an essential trace element". Nutr Clin Pract 8 (6): 277–81. doi:10.1177/0115426593008006277. PMID 8302261.
- ^ "NSC 101 Chapter 8 Content". http://www.nutrition.arizona.edu/nsc101/chap08/ch08.htm. Retrieved 2008-12-02.
- ^ Anke M, Groppel B, Kronemann H, Grün M (1984). "Nickel--an essential element". IARC Sci. Publ. (53): 339–65. PMID 6398286.
- ^ "Linus Pauling Institute at Oregon State University". http://lpi.oregonstate.edu/infocenter/minerals/chromium/. Retrieved 2008-11-29.
- ^ Eastmond DA, Macgregor JT, Slesinski RS (2008). "Trivalent chromium: assessing the genotoxic risk of an essential trace element and widely used human and animal nutritional supplement". Crit. Rev. Toxicol. 38 (3): 173–90. doi:10.1080/10408440701845401. PMID 18324515. http://www.informaworld.com/openurl?genre=article&doi=10.1080/10408440701845401&magic=pubmed%7C%7C1B69BA326FFE69C3F0A8F227DF8201D0.
- ^ Stearns DM (2000). "Is chromium a trace essential metal?". Biofactors 11 (3): 149–62. doi:10.1002/biof.5520110301. PMID 10875302.
- ^ Cerklewski FL (May 1998). "Fluoride--essential or just beneficial". Nutrition 14 (5): 475–6. doi:10.1016/S0899-9007(98)00023-9. PMID 9614319. http://linkinghub.elsevier.com/retrieve/pii/S0899900798000239.
- ^ "Linus Pauling Institute at Oregon State University". http://lpi.oregonstate.edu/infocenter/minerals/fluoride/. Retrieved 2008-11-29.
- ^ "Boron in human and animal nutrition". http://www.springerlink.com/content/r2g8836th0656277/. Retrieved 2010-10-06.
- ^ "The biological role of strontium". http://www.thebonejournal.com/article/S8756-3282(04)00181-4/abstract. Retrieved 2010-10-06.
Categories: Dietary minerals | Nutrition | Food science
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