Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc (2001) / Chapter Skim
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11 Molybdenum
11 Molybdenum
Pages 420-441
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From page 420... ...
The average dietary intake of molybdenum by adult men and women is 109 and 76 Gay, respectively. The Tolerable Upper Intake Level (UL)
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From page 421... ...
Because sulfite is not oxiclizeci to sulfate, severe neurological damage leacling to early cleath occurs with this inborn error of metabolism Johnson, 1997~. Further support for an essential metabolic role for molybclenum relates to amino acid intolerance in a patient who received long-term total parenteral nutrition without molybdenum (Abumraci et al., 1981~.
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From page 422... ...
Biochemical changes inclucleci elevated plasma methionine concentration, low serum uric acid concentration, high urinary thiosulfate, and low urinary uric acid and sulfate. After aciministration of ammonium molybciate, the biochemical abnormalities were reversed.
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From page 423... ...
In molybdenum cofactor deficiency and in the one case of molybdenum deficiency reported, urinary sulfate was low and urinary sulfite was present. Serum uric acid concentrations were low, urinary xanthine and hypoxanthine increased, and plasma methionine was increased (Abumraci et al., 1981; Johnson et al., 1993)
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From page 424... ...
The interaction is not consiclereci to be of significance to humans. There is one report of increased urinary copper excretion with molybdenum intake from sorghum with molybdenum intakes of 500 and 1,500 fig (Deosthale and Gopalan, 1974~.
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Friel and coworkers (1999) found that the molybdenum concentration of human milk of mothers of premature infants ranged from 2.1 to 23 ~g/L with a meclian concentration of ~ CAL.
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From page 426... ...
By using the reference weight ratio method clescribeci in Chapter 2 to extrapolate from the AI for infants ages O through 6 months, the AI is 3 ~g/day after rounding.
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From page 427... ...
Although there are no studies available to indicate that the molybdenum requirement is associated with energy expencliture, metabolic weight (kg0 75) was used for extrapolating because of the functional role of molybdenum in a select number of enzymes, and because using metabolic weight yields an EAR that is higher than when total body weight is used.
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From page 428... ...
A for Boys 9-13 years 14-18 years RI) A for Girls 9-13 years 14-18 years 17 1lg/day of molybdenum 22 1lg/day of molybdenum 341lg/day of molybdenum 431lg/day of molybdenum 341lg/day of molybdenum 431lg/day of molybdenum Adults Ages I 9 Years and Older Evidence Considered in Estimating the Average Requirement The basis for an EAR for molybdenum was molybdenum balance in controlled studies with specific amounts of molybdenum consumeci.
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From page 429... ...
four clays was not sufficiently long to adapt to the clietary molybclenum intake. On the basis of balance ciata and lack of molybdenum deficiency, the average minimum molybdenum requirement for maintaining acloquate molybdenum status is estimated to be 22 ~g/ciay plus an increment for miscellaneous losses.
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From page 430... ...
Molybdenum EAR and RDA Summary, Ages ~ 9 Years and Older EAR for Men 19-50 years 51-70 years > 70 years EAR for Women 19-50 years 51-70 years > 70 years 34 1lg/day of molybdenum 34 1lg/day of molybdenum 34 1lg/day of molybdenum 34 1lg/day of molybdenum 34 1lg/day of molybdenum 34 1lg/day of molybdenum The number of molybdenum levels in the adult clepletion/repletion study was very limited, and the number of subjects was low. Thus, a CV of 15 percent is used; the RDA is clefineci as the EAR plus twice the CV to cover the neecis of 97 to 98 percent of the inclivicluals in the group (therefore, for molybdenum the RDA is set at 130 percent of the EAR)
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From page 431... ...
RI) A for Pregnancy 14-18 years 19-30 years 31-50 years 5Ollg/day of molybdenum 5Ollg/day of molybdenum 5Ollg/day of molybdenum Lactation Evidence Considered in Estimating the Average Requirement The EAR for lactation is estimated as the sum of the molybdenum intake necessary to replace the molybdenum secreted ciaily in human milk and the EAR for adolescent girls and women.
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Usual intake is well above the clietary molybdenum requirement. Intake from Supplements Baseci on ciata from Third National Health and Nutrition Examination Survey (Appendix Table C-21)
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From page 433... ...
In monogastric laboratory animals, molybdenum has been associated with recluceci growth or weight loss, renal failure, skeletal abnormalities, infertility, anemia, diarrhea, and thyroid injury (Vyskocil and Viau, 1999~. Since none of these effects have been observed in humans, it is impossible to determine which ones might be consiclereci most relevant to humans.
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From page 434... ...
Serum molybdenum concentration was positively correlated with serum uric acid concentration. Elevations in blood molybdenum concentrations were accompanied by decreases in blood copper concentrations.
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From page 435... ...
Bioavailability and Toxicokinetics. Possible reasons for the presumed low toxicity of molybdenum include its rapid excretion in the urine, especially at higher intake levels (Miller et al., 1956; Turnlunci et al., l995b)
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From page 436... ...
The NOAEL from that study was 2 ma/ kg/clay. Taken together, these observations suggest that numerous adverse reproductive effects were encountered in rats and mice at clietary molybdenum levels exceeding the NOAEL of 0.9 mg/kg/ clay established from the study of Fungwe and coworkers (1990~.
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From page 437... ...
This level is supported by limited human data from Deosthale and Gopalan (1974) who demonstrated no effect on uric acid or copper excretion in humans exposed to 22 g/kg/day or 1.5 mg/day for an adult.
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From page 438... ...
Molybdenum UT Summary, Ages O through IS Years, Pregnancy, Lactation UL for Infants 0-12 months UL for Children 1-3 years 4-8 years 9-13 years UL for Adolescents 14-18 years UL for Pregnancy 14-18 years 19-50 years UL for Lactation 14-18 years 19-50 years Special Considerations Inclivicluals who are deficient in clietary copper intake or have some dysfunction in copper metabolism that makes them coppercleficient could be at increased risk of molybdenum toxicity. However, the effect of molybdenum intake on copper status in humans remains to be clearly established.
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From page 439... ...
1996. Trace element content in human milk during lactation of preterm newborns.
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1998. Changes in the concentrations of trace elements in human milk during lactation.
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From page 441... ...
1995a. Molybdenum absorption, excretion, and retention studied with stable isotopes in young men at five intakes of dietary molybdenum.
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