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jan 11

significance of zinc

The number of redox centers in some Mo-proteins exceeds the number of electrons transferred; reasons for this are unknown currently. Breast milk provides sufficient zinc (2 mg/day) for the first 4–6 months of life but does not provide recommended amounts of zinc for infants aged 7–12 months, who need 3 mg/day [2,36]. The transition metals and zinc are among the least abundant metal ions in the sea water from which contemporary organisms are thought to have evolved (Table 1.1).1-5 For many of the metals, the concentration in human blood plasma greatly exceeds that in sea water. Zinc can reduce the absorption and action of penicillamine, a drug used to treat rheumatoid arthritis [92]. Several important functions of zinc include: Making DNA and RNA, which is important to actively dividing cells Zinc sulfate is used to treat and to prevent zinc deficiency. Position of the American Dietetic Association and Dietitians of Canada: vegetarian diets. [, Meydani SN, Barnett JB, Dallal GE, Fine BC, Jacques PF, Leka LS, et al. [, Fischer Walker CL, Black RE. In addition, results from a pooled analysis of randomized controlled trials of zinc supplementation in developing countries suggest that zinc helps reduce the duration and severity of diarrhea in zinc-deficient or otherwise malnourished children [65]. Foods providing 20% or more of the DV are considered to be high sources of a nutrient, but foods providing lower percentages of the DV also contribute to a healthful diet. The most common type of reaction in which cobalamin enzymes participate results in the reciprocal exchange of hydrogen atoms if they are on adjacent carbon atoms, yet not with hydrogen in solvent water: (An important exception is the ribonucleotide reductase from some bacteria and lower plants, which converts ribonucleotides to the DNA precursors, deoxyribonucleotides, a reaction in which a sugar -OH is replaced by -H. Note that ribonucleotide reductases catalyzing the same reaction in higher organisms and viruses are proteins with an oxo-bridged dimeric iron center.) It’s important for healing injuries and creating DNA, the genetic blueprint in all of your cells. J Nutr 2003;133:1485S-9S. Zinc and immune function: the biological basis of altered resistance to infection. Zinc is a common element in nucleic-acid polymerases and transcription factors, where its role is considered to be structural rather than catalytic. Zinc is a nutrient that plays many vital roles in your body. Zinc is involved in numerous aspects of cellular metabolism. However, because AREDS2 had fewer participants than the original AREDS study, and fewer than half took the lower zinc formula, the researchers view this finding as preliminary. Among the transition metals used in living organisms, iron is the most abundant in the environment. In: Shils ME, Shike M, Ross AC, Caballero B, Cousins, RJ, eds. [Article in German] Seeling W, Ahnefeld FW, Dick W, Fodor L. Zinc takes part in the catalytic function of many metalloenzymes. Int J Food Sci Nutr 1995;46:53-63. Am J Clin Pathol 2005;123:125-31. Zinc is an essential mineral that is naturally present in some foods, added to others, and available as a dietary supplement. In more severe cases, zinc deficiency causes hair loss, diarrhea, delayed sexual maturation, impotence, hypogonadism in males, and eye and skin lesions [2,8,27,28]. Lutein + zeaxanthin and omega-3 fatty acids for age-related macular degeneration: the Age-Related Eye Disease Study 2 (AREDS2) randomized clinical trial. Washington, DC: U.S. Department of Agriculture, Economic Research Service. The superoxide dismutase of bacteria and mitochondria, as well as pyruvate carboxylase in mammals, are also manganese proteins.16,17 How the multiple manganese atoms of the photosynthetic reaction center participate in the removal of four electrons and protons from water is the subject of intense investigation by spectroscopists, synthetic inorganic chemists, and molecular biologists.17. [, Lewis MR, Kokan L. Zinc gluconate: acute ingestion. Food Labeling: Revision of the Nutrition and Supplement Facts Labels and Serving Sizes of Foods That Can Reasonably Be Consumed at One Eating Occasion; Dual-Column Labeling; Updating, Modifying, and Establishing Certain Reference Amounts Customarily Consumed; Serving Size for Breath Mints; and Technical Amendments; Proposed Extension of Compliance Dates. All the Ni-proteins known to date are from plants or bacteria.13,14 However, about 50 years elapsed between the crystallization of jack-bean urease in 1925 and the identification of the nickel component in the plant protein. [, Nishi Y. Zinc and growth. [, Bhutta ZA, Bird SM, Black RE, Brown KH, Gardner JM, Hidayat A, et al. These reactions are fundamental to life and biological activity. J Nutr 2002;132:3422-7. [, Shankar AH, Prasad AS. Zinc is a mineral. Techniques to increase zinc bioavailability include soaking beans, grains, and seeds in water for several hours before cooking them and allowing them to sit after soaking until sprouts form [41]. Have questions or comments? [, Navarro S, Valderrama R, To-Figueras J, Gimenez A, Lopez JM, Campo E, et al. J Nutr 2001;131:1232-46. Intake recommendations for zinc and other nutrients are provided in the Dietary Reference Intakes (DRIs) developed by the Food and Nutrition Board (FNB) at the Institute of Medicine of the National Academies (formerly National Academy of Sciences) [2]. [, Anderson I. Zinc as an aid to healing. Zinc gluconate may also be used for other purposes not listed in this medication guide. Long-term intakes above the UL increase the risk of adverse health effects [2]. Aside from dietary zinc supplementation, zinc has been st… Nutr Rev 1998;56:27-8. J Toxicol Clin Toxicol 1998;36:99-101. Acta Med Scand 1980;208:209-12. Clinical management of acute diarrhoea. Zinc deficiency: a special challenge. High zinc intakes can inhibit copper absorption, sometimes producing copper deficiency and associated anemia [84,85]. AREDS2 found that a formulation providing 25 mg zinc (about one-third the amount in the original formulation) provided the same protective effect against developing advanced AMD. )%2F01%253A_Transition-Metal_Storage_Transport_and_Biomineralization%2F1.01%253A_Biological_Significance_of_Iron_Zinc_Copper_Molybdenum_Cobalt_Chromium_Vanadium_and_Nickel, 1: Transition-Metal Storage, Transport, and Biomineralization, information contact us at info@libretexts.org, status page at https://status.libretexts.org. Zinc is an important trace mineral that people need to stay healthy. [, Lomaestro BM, Bailie GR. Ervin RB, Kennedy-Stephenson J. Much of the zinc in animals and plants has no known function, but it may be maintaining the structures of proteins that activate and deactivate genes.11. Clinical and laboratory assessment of zinc deficiency in Dutch children. In fact, almost 20 metalloenzymes have an active site formed through zinc. Nurs Times 1995;91:68, 70. In June 2009, the FDA warned consumers to stop using three zinc-containing intranasal products because they might cause anosmia [19]. In addition to breast milk, infants aged 7–12 months should consume age-appropriate foods or formula containing zinc [2]. [, Van Wouwe JP. Cochrane Database Syst Rev 2006;(2):CD000254. Zinc is important for growth and for the development and health of body tissues. When metals compete: a case of copper-deficiency myeloneuropathy and anemia. Researchers have suggested that both zinc and antioxidants delay the progression of age-related macular degeneration (AMD) and vision loss, possibly by preventing cellular damage in the retina [74,75]. A meta-analysis of the effects of oral zinc in the treatment of acute and persistent diarrhea. [, Stur M, Tittl M, Reitner A, Meisinger V. Oral zinc and the second eye in age-related macular degeneration. 1986 Jul;31(7):724-31. Numerous case reports of anosmia (loss of the sense of smell), in some cases long-lasting or permanent, have been associated with the use of zinc-containing nasal gels or sprays [17,18]. Sandstead HH. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. In addition to standard tablets and capsules, some zinc-containing cold lozenges are labeled as dietary supplements. 2009 Feb;5(2):106-11. Oysters contain more zinc per serving than any other food, but red meat and poultry provide the majority of zinc in the American diet. Unless otherwise noted, LibreTexts content is licensed by CC BY-NC-SA 3.0. The cobalt in vitamin B12 is coordinated to five N atoms, four contributed by a tetrapyrrole (corrin); the sixth ligand is C, provided either by C5 of deoxyadenosine in enzymes such as methylmalonyl-CoA mutase (fatty acid metabolism) or by a methyl group in the enzyme that synthesizes the amino acid methionine in bacteria. [, Ribar DS, Hamrick KS. Iron is the most common transition metal in biology.6,7 Its use has created a dependence that has survived the appearance of dioxygen in the atmosphere ca. Join the ODS Email List. Proc Assoc Am Physicians 1997;109:68-77. In addition, the variety and amount of food consumed by many alcoholics is limited, leading to inadequate zinc intake [2,49,50]. Whether any types of biological reactions are unique to copper proteins is not clear. Clinicians consider risk factors (such as inadequate caloric intake, alcoholism, and digestive diseases) and symptoms of zinc deficiency (such as impaired growth in infants and children) when determining the need for zinc supplementation [2]. Zinc deficiency also affects approximately 60%–70% of adults with sickle cell disease [47]. [, Broun ER, Greist A, Tricot G, Hoffman R. Excessive zinc ingestion. [, Wilkinson EA, Hawke CI. [, Prasad AS. Zinc for the common cold. Vanadium is required for normal health, and could act in vivo either as a metal cation or as a phosphate analogue, depending on the oxidation state, V(lV) or V(V), respectively. The elemental zinc content appears in the Supplement Facts panel on the supplement container. Supplemental zinc might also be appropriate in certain situations. [, van Leeuwen R, Boekhoorn S, Vingerling JR, Witteman JC, Klaver CC, Hofman A, et al. Currently, these safety concerns have not been found to be associated with cold lozenges containing zinc. Research has not determined whether differences exist among forms of zinc in absorption, bioavailability, or tolerability. Am J Clin Nutr 1998;68 (2 Suppl):499S-508S. Includes a variety of vegetables, fruits, whole grains, fat-free or low-fat milk and milk products, and oils. Send all comments or additions to: Frankp@chiro.org FROM: Anaesthesist 1975 (Aug); 24 (8): 329–342 Seeling W, Ahnefeld FW, Dick W, Fodor L [, Kang YJ, Zhou Z. Zinc prevention and treatment of alcoholic liver disease. Cochrane Database Syst Rev. Ann Nutr Metab 2007;51:301-23. J Infect Dis 2008 ;197:795-802. However, more research is needed to determine the optimal dosage, zinc formulation and duration of treatment before a general recommendation for zinc in the treatment of the common cold can be made [73]. [, Wintergerst ES, Maggini S, Hornig DH. In zinc deficient animals protein synthesis is disturbed. [. Zinc supplementation significantly reduced visual acuity loss in one of the studies [81] but had no effect in the other [82]. The percentage of elemental zinc varies by form. In a randomized, double-blind, placebo-controlled clinical trial, 50 subjects (within 24 hours of developing the common cold) took a zinc acetate lozenge (13.3 mg zinc) or placebo every 2–3 wakeful hours. [The biological significance of zinc (author's transl)]. Zinc is widely used for plating that imparts corrosion resistant upper layer to various metals. For infants aged 0 to 6 months, the FNB established an AI for zinc that is equivalent to the mean intake of zinc in healthy, breastfed infants. The metals are generally found either bound directly to proteins or in cofactors such as porphyrins or cobalamins, or in clusters that are in turn bound by the protein; the ligands are usually O, N, S, or C. Proteins with which transition metals and zinc are most commonly associated catalyze the intramolecular or intermolecular rearrangement of electrons. 0; Significance of Zinc in a human body. Pediatrics 2008;121:326-36. Data from NHANES III indicate that adults aged 60 years or older from food-insufficient families had lower intakes of zinc and several other nutrients and were more likely to have zinc intakes below 50% of the RDA on a given day than those from food-sufficient families [26]. The DV for zinc on the new Nutrition Facts and Supplement Facts labels and used for the values in Table 2 is 11 mg for adults and children aged 4 years and older [15]. Individuals with low zinc levels have shown reduced lymphocyte proliferation response to mitogens and other adverse alterations in immunity that can be corrected by zinc supplementation [52,54]. Met Ions Biol Syst 2004;41:103-37. [. Zinc is a critical component of the catalytic site of hundreds of kinds of different metalloenzymes in each human being. J Trop Pediatr 1997;43:192-8. Zinc deficiency in women, infants and children. Zinc helps maintain the integrity of skin and mucosal membranes [52]. Zinc gluconate is used to treat and to prevent zinc deficiency. [. The U.S. Department of Agriculture's (USDA's) FoodData Central [11] lists the nutrient content of many foods and provides a comprehensive list of foods containing zinc arranged by nutrient content and by food name. U.S. Department of Agriculture, Agricultural Research Service. Chromium imbalance affects sugar metabolism and has been associated with the glucose tolerance factor in animals. Interestingly, certain bacteria (Azotobacter) have alternative nitrogenases, which are produced when molybdenum is deficient and which contain vanadium and iron or only iron. Effect of zinc sulphate on the absorption of tetracycline and doxycycline in man. It serves as an enzyme cofactor and protects cell membranes from lysis caused by complement activation and toxin release. Neurology. A few examples are provided below. [, Ploysangam A, Falciglia GA, Brehm BJ. Updated: July 15, 2020 History of changes to this fact sheet, U.S. Department of Health & Human Services, Strengthening Knowledge and Understanding of Dietary Supplements, My Dietary Supplement and Medicine Record, How To Evaluate Health Information on the Internet, NIH Consortium for Advancing Research on Botanical and Other Natural Products (CARBON) Program, Analytical Methods and Reference Materials (AMRM), Dietary Supplement Ingredient Database (DSID), Computer Access to Research on Dietary Supplements (CARDS) Database, Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc, Guidance for Industry: A Food Labeling Guide. Intakes of 150–450 mg of zinc per day have been associated with such chronic effects as low copper status, altered iron function, reduced immune function, and reduced levels of high-density lipoproteins [87]. FDA required manufacturers to use these new labels starting in January 2020, but companies with annual sales of less than $10 million may continue to use the old labels that list a zinc DV of 15 mg until January 2021 [14,16]. 1995 update. However, use of stored iron is reduced by copper deficiency, which suggests that iron metabolism may depend on copper proteins, such as the serum protein ceruloplasmin, which can function as a ferroxidase, and the cellular protein ascorbic acid oxidase, which also is a ferrireductase. Because your body doesn’t naturally produce zinc, you must obtain it through food or … Several studies are described below in which zinc is administered as a lozenge or zinc-containing syrup that temporarily "sticks" in the mouth and throat. Phytates—which are present in whole-grain breads, cereals, legumes, and other foods—bind zinc and inhibit its absorption [2,12,13]. Chronic diarrhea also leads to excessive loss of zinc [27]. Food Labeling: Revision of the Nutrition and Supplement Facts Labels. [, Hulisz D. Efficacy of zinc against common cold viruses: an overview. A review. All plants, animals, and bacteria use iron, except for a lactobacillus that appears to maintain high concentrations of manganese instead of iron. Brass supplemented bronze during the Roman Empire in the manufacture of coins, weapons, and art. Fortification of foods with iron does not significantly affect zinc absorption. Thus, the bioavailability of zinc from grains and plant foods is lower than that from animal foods, although many grain- and plant-based foods are still good sources of zinc [2]. [, Beck FW, Prasad AS, Kaplan J, Fitzgerald JT, Brewer GJ. It is required for the catalytic activity of approximately 100 enzymes [1,2] and it plays a role in immune function [3,4], protein synthesis [4], wound healing [5], DNA synthesis [2,4], and cell division [4]. Meat and seafood are rich in zinc.1, 2 The role of zinc in human health and functioning has primarily focused on dietary supplementation for the promotion of health and disease prevention. Arch Ophthalmol 1988;106:192-8. Food Assistance and Nutrition Report Number 36, 2003. The Age-Related Eye Disease Study (AREDS), a large, randomized, placebo-controlled, clinical trial (n = 3,597), evaluated the effect of high doses of selected antioxidants (500 mg vitamin C, 400 IU vitamin E, and 15 mg beta-carotene) with or without zinc (80 mg as zinc oxide) on the development of advanced AMD in older individuals with varying degrees of AMD [75]. Brown KH, Allen LH, Peerson J. Zinc supplementation and children's growth: a meta-analysis of intervention trials. Washington, DC: U.S. Government Printing Office, 1995. Zinc deficiency is characterized by growth retardation, loss of appetite, and impaired immune function. Kids need to get enough zinc in their diets because of its influence on cell development, meaning a lack of … Clinical Significance. Zinc deficiency, infectious disease and mortality in the developing world. Acute adverse effects of high zinc intake include nausea, vomiting, loss of appetite, abdominal cramps, diarrhea, and headaches [2]. Zinc nutritional status is difficult to measure adequately using laboratory tests [2,34,35] due to its distribution throughout the body as a component of various proteins and nucleic acids [36]. For example, approximately 23% of zinc sulfate consists of elemental zinc; thus, 220 mg of zinc sulfate contains 50 mg of elemental zinc. For this reason, dietary supplement formulations containing high levels of zinc, such as the one used in the AREDS study [75], sometimes contain copper. A follow-up AREDS2 study confirmed the value of this supplement in reducing the progression of AMD over a median follow-up period of 5 years [78]. Zinc deficiency in patients with sickle cell disease. Am J Clin Nutr 1998;68 (2 Suppl):509S -12S. Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice. When the investigators considered intakes from both food and dietary supplements, they found that 20%–25% of older adults still had inadequate zinc intakes [24]. The body requires zinc to develop and activate T-lymphocytes [2,53]. Zinc is a key element required for active wound healing. Plasma or serum zinc levels are the most commonly used indices for evaluating zinc deficiency, but these levels do not necessarily reflect cellular zinc status due to tight homeostatic control mechanisms [8]. Ask ODS Reductions in a copper-containing enzyme, a marker of copper status, have been reported with even moderately high zinc intakes of approximately 60 mg/day for up to 10 weeks [2]. Zinc is a bluish-white metal which is used to make other metals, or to cover other metals, such as steel, as a protective coating. [, Turner RB, Cetnarowski WE. FDA does not require food labels to list zinc content unless zinc has been added to the food. Serum zinc and pneumonia in nursing home elderly. Intranasal zinc and anosmia: the zinc-induced anosmia syndrome. Supports progression and the healthy Zinc was first shown to be required for the growth of the mold Aspergillus niger by Raulin in 1869. [. Results from a large cross-sectional survey suggest that 44% of children with sickle cell disease have a low plasma zinc concentration [45], possibly due to increased nutrient requirements and/or poor nutritional status [46]. Zinc supplementation alone significantly reduced the risk of developing advanced AMD in subjects at higher risk but not in the total study population. Gastrointestinal surgery and digestive disorders (such as ulcerative colitis, Crohn's disease, and short bowel syndrome) can decrease zinc absorption and increase endogenous zinc losses primarily from the gastrointestinal tract and, to a lesser extent, from the kidney [2,29,38,39]. Biological Significance of Zinc The zinc atomic structure plays an integral role in every other living organism. Upon reducing cellular zinc, repression is lost and MTF-1 is not translocated to the nucleus, allowing enhanced ZIP10 transcriptional activation. liver both during zinc restriction and zinc excess. [, Lukacik M, Thomas RL, Aranda JV. Am J Clin Nutr 1998;68:442S-6S. Clinical effects of zinc deficiency can be present in the absence of abnormal laboratory indices [8]. [, Brewer GJ, Yuzbasiyan-Gurkan V, Johnson V, Dick RD, Wang Y. Vanadium and chromium have several features in common, from a bioinorganic viewpoint.18a First, both metals are present in only small amounts in most organisms. Eur J Clin Pharmacol 1975;9:131-4. Zinc also supports normal growth and development during pregnancy, childhood, and adolescence [6-8] and is required for proper sense of taste and smell [9]. Am J Physiol 1997;272:E1002-7. Scand J Gastroenterol 1998;33:514-23. ... Foods in nutrient-dense forms contain essential vitamins and minerals and also dietary fiber and other naturally occurring substances that may have positive health effects. Zinc deficiency: its characterization and treatment. Researchers have hypothesized that zinc could reduce the severity and duration of cold symptoms by directly inhibiting rhinovirus binding and replication in the nasal mucosa and suppressing inflammation [68,69]. [, Krebs NF. New York, NY: Springer-Verlag, 1989:281-96. One study demonstrated that after restricting the zinc intake of the participants for 5 months, supplementing with zinc had a significant impact on testosterone levels in the majority of participants. Contribution of selected vitamins and trace elements to immune function. This is a fact sheet intended for health professionals. Pregnant women, particularly those starting their pregnancy with marginal zinc status, are at increased risk of becoming zinc insufficient due, in part, to high fetal requirements for zinc [42]. Ann Pharmacother 1996;30:186-7. The peptidases, kinases, and phosphorylases are most sensitive to zinc depletion. DRI is the general term for a set of reference values used for planning and assessing nutrient intakes of healthy people. Effects of zinc deficiency on Th1 and Th2 cytokine shifts. However, treatment with zinc acetate lozenges (providing 5 or 11.5 mg zinc) had no effect on either cold duration or severity. 2011 Feb 16;2:CD001364. King JC, Cousins RJ. BMJ 2007;335:755. Zinc is a mineral that your body uses for fighting off infections and producing cells. Effect of weekly zinc supplements on incidence of pneumonia and diarrhoea in children younger than 2 years in an urban, low-income population in Bangladesh: randomised controlled trial. Zinc is an essential trace element that activates several hundred enzymatic reactions. JAMA 2013;309:2005-15. Taking iron supplements between meals helps decrease its effect on zinc absorption [83]. Third Report on Nutrition Monitoring in the United States. Cochrane Database Syst Rev 2000;(2):CD001273. Alcohol Clin Exp Res 1994;18:895-901. Although studies examining the effect of zinc treatment on cold symptoms have had somewhat conflicting results, overall zinc appears to be beneficial under certain circumstances. Therapeutic effects of oral zinc in acute and persistent diarrhea in children in developing countries: pooled analysis of randomized controlled trials. The objective of this paper is to provide a current overview of the significance of zinc in human nutrition. Such data indicate the importance of mechanisms for accumulation, storage, and transport of transition metals and zinc in living organisms. [, Penttilä O, Hurme H, Neuvonen PJ. 8. Zinc in Human Biology. [, Prasad AS. A Cochrane review concluded that the evidence supporting the use of antioxidant vitamins and zinc for AMD comes primarily from the AREDS study [74]. Dermatology 1996;193:361-3. Micronutrients and diarrheal disease. Aging (Milano) 1995;7:77-93. For more information about building a healthy diet, refer to the Dietary Guidelines for Americans and the U.S. Department of Agriculture's MyPlate. However, research has not shown that the general use of zinc sulfate in patients with chronic leg ulcers or arterial or venous ulcers is effective [61,62]. [, Prasad AS. The zinc present in the pancreas may aid in the storage of insulin. [, Prasad AS. Definition of 'Zinc' Definition: Zinc has a bluish white color which stands fourth in the list of most commonly used metals. 1.1: Biological Significance of Iron, Zinc, Copper, Molybdenum, Cobalt, Chromium, Vanadium, and Nickel, https://chem.libretexts.org/@app/auth/2/login?returnto=https%3A%2F%2Fchem.libretexts.org%2FBookshelves%2FInorganic_Chemistry%2FBook3A_Bioinorganic_Chemistry_(Bertini_et_al.

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