Essential nutrient



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An essential nutrient is a essential amino acids.

Different species have very different essential nutrients. Most essential nutrients are substances that are metabolically necessary but cannot be synthesized by the organism. hemoglobin from their diet. Of course, this iron is recycled, but some is inevitably lost, for example during menstruation.

Many essential nutrients are toxic in large doses (see hypervitaminosis or the nutrient pages themselves below). Some can be taken in amounts larger than required in a typical diet, with no apparent ill effects. Linus Pauling said of vitamin B3, (either niacin or niacinamide), "What astonished me was the very low toxicity of a substance that has such very great physiological power. A little pinch, 5 mg, every day, is enough to keep a person from dying of pellagra, but it is so lacking in toxicity that ten thousand times as much can [sometimes] be taken without harm." [1] A similar statement can be made about vitamins.

List of essential nutrients

The body's requirements vary widely. At one extreme a 70 kg human contains 1.0 kg of calcium but only 3 mg of cobalt or 0.5 mg of bismuth.[8]

Elements with speculated role in human health

Many elements have been implicated at various times to have a role in human health. For none of these elements has the specific protein or complex been identified:

References

  1. ^ Pauling, L. (1986). How to Live Longer and Feel Better. New York NY 10019: Avon Books Inc.. ISBN 0-380-70289-4.  Page 24.
  2. ^ R. Bruce Martin “Metal Ion Toxicity” in Encyclopedia of Inorganic Chemistry, Robert H. Crabtree (Ed), John Wiley & Sons, 2006. DOI: 10.1002/0470862106.ia136
  3. ^ Hausman, p. 467
  4. ^ Hausman, p. 469
  5. ^ Hausman, p. 470
  6. ^ Hausman, p. 432
  7. ^ Hausman, p. 395
  8. ^ http://web2.airmail.net/uthman/elements_of_body.html
  9. ^ a b c d Mertz, W. 1974. The newer essential trace elements, chromium, tin, vanadium, nickel and silicon. Proc. Nutr. Soc. 33 p. 307.

Further reading

  • Hausman, P, 1987, The Right Dose. Rodale Press, Emaus, Pennsylvania. ISBN 0-87857-678-9

See also

 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Essential_nutrient". A list of authors is available in Wikipedia.