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dietary mineral

 
 
Columbia Encyclopedia: dietary mineral
mineral, dietary, any of a group of inorganic elements that are essential to humans and animals for normal body function. In nutrition, minerals are those elements for which the body's requirement is at least 100 mg per day, and trace minerals are those elements that are needed in smaller amounts. Dietary minerals are derived from the earth's crust. Plants extract the minerals from the soil, and humans and animals, in their turn, consume the plants. There are seven major minerals. Calcium occurs mainly in the teeth and bones, but a small amount is found in blood plasma and other body fluids, where it influences nerve transmission, blood clotting, and muscle contraction. Dairy products and green leafy vegetables are dietary sources of calcium, and an adequate intake of vitamin D is required for calcium absorption. Phosphorus, also found in dairy products, is closely allied to calcium in bone and tooth formation and its association with vitamin D. It is present in every cell in compounds such as nucleic acids and adenosine triphosphate. Magnesium, also present in every cell, is necessary for carbohydrate and protein metabolism, cell reproduction, and smooth muscle action. Dietary sources include nuts, soy beans, and cocoa. Sodium is in the skeleton and extracellular fluids and is necessary for fluid and acid-base balance, cell permeability, and muscle function. It occurs in table salt (sodium chloride, the main source) and such foods as milk and spinach. Potassium, which is found in intra- and extracellular fluid, plays a major role in fluid and electrolyte balance and in heart muscle activity, and is also required for carbohydrate metabolism and protein synthesis. Its sources include legumes, whole grains, and bananas. Chlorine is found in extracellular fluid, where it helps maintain normal fluid-electrolyte and acid-base balance, and in the stomach, where it helps provide the acidic environment necessary for digestion. Table salt is its main dietary source. Sulfur, which is important to the structure of proteins, is also necessary for energy metabolism, enzyme function, and detoxification. Sulfur is obtained from protein foods, such as meat, eggs, and legumes. Some trace minerals are considered "essential" in human nutrition. The essential trace minerals include iron, which is a constituent of hemoglobin; iodine, which is necessary for thyroxine synthesis; and cobalt, which is a component of vitamin B12. Other essential trace minerals are chromium, copper, fluorine, manganese, molybdenum, selenium, and zinc.


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Health Dictionary: minerals
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In the diet, certain substances necessary for the maintenance of life and good health. Some are essential components of bodily substances, such as the calcium in bones and the iron in hemoglobin, whereas others help regulate the activities of metabolism. (See under “Earth Sciences.”)

Wikipedia: Dietary mineral
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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 ions, not chemical compounds or actual minerals.

Dietitians may recommend that minerals are best supplied by ingesting specific foods rich with the element(s) of interest. Sometimes minerals are ingested as mineral dietary supplements, the most common being iodine in iodized salt.

The dietary focus on minerals derives from an interest in supporting biochemical reactions with the required elemental components.[1] Appropriate intake levels of certain chemical elements are thus required to maintain optimal health. According to nutritional experts, the requirements are met simply with a conventional balanced diet.[citation needed]

Contents

Essential minerals

Some sources state that sixteen minerals are required to support human biochemical processes by serving structural and functional roles as well as electrolytes:[2] Sometimes a distinction is drawn between this category and micronutrients. Most of the essential minerals are of relatively low atomic weight:

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:

Mineral 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
Chloride 2300 mg Quantity is needed for production of hydrochloric acid in the stomach and in cellular pump functions. Table salt is the main dietary source of chloride. 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) and 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. 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. 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 for the biosynthesis of thyroxine. iodine deficiency
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]

  • 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.
  • There have been occasional studies asserting the essentiality of nickel,[7] but it currently has no known RDA.
  • 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]
  • Fluoride has been described as conditionally essential, depending upon the importance placed upon the prevention of chronic disease.[11][12]

See also

External links

References

  1. ^ a b Lippard, Stephen J.; Jeremy M. Berg (1994). Principles of Bioinorganic Chemistry. Mill Valley, CA: University Science Books. pp. 411. ISBN 0935702725. 
  2. ^ 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. 
  3. ^ 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. 
  4. ^ "Linus Pauling Institute at Oregon State University". http://lpi.oregonstate.edu/infocenter/minerals/phosphorus/. Retrieved 2008-11-29. 
  5. ^ Sardesai VM (December 1993). "Molybdenum: an essential trace element". Nutr Clin Pract 8 (6): 277–81. doi:10.1177/0115426593008006277. PMID 8302261. 
  6. ^ "NSC 101 Chapter 8 Content". http://www.nutrition.arizona.edu/nsc101/chap08/ch08.htm. Retrieved 2008-12-02. 
  7. ^ Anke M, Groppel B, Kronemann H, Grün M (1984). "Nickel--an essential element". IARC Sci. Publ. (53): 339–65. PMID 6398286. 
  8. ^ "Linus Pauling Institute at Oregon State University". http://lpi.oregonstate.edu/infocenter/minerals/chromium/. Retrieved 2008-11-29. 
  9. ^ 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||1B69BA326FFE69C3F0A8F227DF8201D0. 
  10. ^ Stearns DM (2000). "Is chromium a trace essential metal?". Biofactors 11 (3): 149–62. doi:10.1002/biof.5520110301. PMID 10875302. 
  11. ^ Cerklewski FL (May 1998). "Fluoride--essential or just beneficial". Nutrition 14 (5): 475–6. PMID 9614319. http://linkinghub.elsevier.com/retrieve/pii/S0899900798000239. 
  12. ^ "Linus Pauling Institute at Oregon State University". http://lpi.oregonstate.edu/infocenter/minerals/fluoride/. Retrieved 2008-11-29. 

 
 

 

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