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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5 Vitamin K
5 Vitamin K
Pages 162-196
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From page 162... ...
No adverse effect has been reported for inclivicluals consuming higher amounts of vitamin K, so a Tolerable Upper Intake Level (UL) was not established.
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From page 163... ...
A clepenclence of plasma phylloquinone concentrations (Kohlmeier et al., 1995) on the distribution of lipoprotein apoE isoforms suggests that the vitamin enters the liver through the enclocytosis of chylomicron remnants.
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From page 164... ...
C11inica11 Effects of Inadequate Intake A clinically significant vitamin K deficiency has usually been clefineci as a vitamin K-responsive hypoprothrombinemia and is associateci with an increase in prothrombin time (PT) and, in severe cases, bleeding.
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From page 165... ...
All other indicators have been shown to respond to alterations in clietary vitamin K, but the physiological significance of these cliet-incluceci changes is lacking. Therefore, these indicators have been used to assess relative changes in vitamin K status but do not provide, by themselves or collectively, an acloquate basis on which to estimate an average requirement for vitamin K Prothrombin Time The classical PT used to measure the procoagulant potential of plasma is not a sensitive indicator of vitamin K status because plasma prothrombin concentration must be clecreaseci by approximately 50 percent before a value is outside of the "normal" range (Suttie, 1992~.
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From page 166... ...
phylloquinone concentration may not reflect normal clietary intake. Positive correlations between circulating phylloquinone concentration and dietary intake have been reported, but the strength of this association has varied according to studies, possibly clue to differences in intake assessment methodology (i.e., number of cliet record clays)
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From page 167... ...
Urinary Gla excretion clecreaseci 22 percent after 3 weeks and returned to baseline values 12 clays after supplementation with 50 or 500 fig of phylloquinone. In a recent study, increasing phylloquinone intakes from 100 ~g/ciay to a range of 377 to 417 ~g/ciay for ~ clays clici not induce significant changes in urinary Gla (Booth et al., 1999a)
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From page 168... ...
A number of immunochemical assays, which are very sensitive and are capable of measuring very small increases of this indicator of vitamin K insufficiency, are now commercially available. Typically, these kits will detect changes of a few ng/mL whereas plasma prothrombin concentration averages 100 ~g/mL.
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From page 169... ...
However, a number of issues must be consiclereci before a minimal ucOC concentration can be used as an indicator to estimate an average requirement for vitamin K Because osteocalcin is used clinically as a marker of bone turnover, there are a number of commercial kits currently marketed.
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From page 170... ...
Although there is little doubt that vitamin K intake affects the degree of osteocalcin \-carboxylation, the technical problems associateci with the current assays and the uncertainty surrounding the physiological significance of cliet-incluceci changes prevent the use of ucOC for estimating an average requirement for vitamin K Relationship of Vitamin KIntake to Chronic Disease Vitamin K and Osteoporosis The possibility that vitamin K may have a role in osteoporosis was first suggested with reports of lower circulating phylloquinone concentrations in osteoporotic patients having suffered a spinal crush fracture or fracture of the femur (Hart et al., 1985; Hodges et al., 1991, 1993~.
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From page 171... ...
When the risk of hip fracture was related to levels of ucOC, increased baseline ucOC levels were associated with increaseci hip fracture risk with an ocicis ratio of 2. Although it is not possible to calculate carboxylateci osteocalcin by quartiles from the ciata presented, this biologically active form of osteocalcin was not recluceci in the hip fracture group.
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From page 172... ...
to osteoporotic patients for 6 months was associated with an increase in metacarpal bone density, increaseci total osteocalcin, and recluceci urinary calcium excretion. Interestingly, MK-4 treatment was associated with increased parathyroici hormone and haci no effect on BMD of the lumbar spine (Orimo et al., 1992~.
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From page 173... ...
A role of vitamin K in vascular health is supported by the fincling of extensive arterial calcification in the matrix Gla protein knockout mouse (Luo et al., 1997~. Whether vitamin K status within the range of normal intake plays a significant role in the development of atherosclerosis requires further investigation and should be verified in studies using rigorous experimental designs.
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From page 174... ...
Although direct measures of bioavailabilty have not been reported, a recent study reported no difference in fasting plasma phylloquinone concentrations when 400 fig of phylloquinone as broccoli or as phylloquinone-fortifieci oil was acicleci to a cliet containing 100 fig of phylloquinone (Booth et al., 1999a)
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From page 175... ...
with approximately 360 mg/ciay (400 IU/day) of oc-tocopherol resulted in nonstatistically significant decreases in prothrombin concentrations over a 4-week period, and a statistically significant decrease in the ratio of biologically active prothrombin to prothrombin antigen (Corrigan and Ulfers, 1981~.
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From page 176... ...
of leukemia and other forms of cancer in children who haci received vitamin K intramuscularly at birth. Subsequent studies conclucteci in the United States and European countries (Ansell et al., 1996; Ekelund et al., 1993; Klebanoff et al., 1993; Olsen et al., 1994; von Kries et al., 1996)
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From page 177... ...
Milk intake appears to be an important factor in the etiology of late HDNB as inverse correlations have been reported between human milk intake and undercarboxylated prothrombin (Motohara et al., 1989; von Kries et al., 1987a)
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From page 178... ...
The AI is significantly lower than recently reported intakes based on the Food and Drug Administration Total Diet Study of 77 fig/ day (Booth et al., 1996b) and 111 ~g/day (Appendix Table Em.
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From page 179... ...
Vitamin KAl Summary, Ages O through I2 Months AI for Infants 0-6 months 7-12 months Specia11 Considerations Human milk cloes not contain as much vitamin K as cow milk (5 ~g/mL) or infant formulas (50-100 ~g/L)
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From page 180... ...
The significant increase in the AI from infancy to early chilc~hooci is most likely clue to the method used to set the AI for older infants and the increased portion of the diet containing vitamin K-rich fruits and vegetables as the cliet becomes more cliversifieci. Vitamin KAl Summary, Ages ~ through IS Years AI for Children 1-3 years 4-8 years AI for Boys 9-13 years 14-18 years AI for Girls 30 1lg/day of vitamin K 55 1lg/day of vitamin K 60 1lg/day of vitamin K 75 1lg/day of vitamin K 9-13 years 60 1lg/day of vitamin K 14-18 years 75 1lg/day of vitamin K Adults Ages I 9 Years and Older Method Used to Set the Adequate Intake Clinically significant vitamin K deficiency is extremely rare in the general population, with cases being limited to inclivicluals with malabsorption syndromes or those treated with drugs known to interfere with vitamin K metabolism.
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From page 181... ...
In a recent paper, Booth and Suttie (1998) reviewoci 11 studies in which phylloquinone intakes ranged from 61 to 210 ~g/ciay with average intakes of approximately 80 ~g/ciay for adults younger than 45 years and approximately 150 ~g/ciay for adults older than 55 years (Table 5-2~.
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From page 182... ...
Vitamin KAl Summary, Ages I 9 Years and Older AI for Men 19-30 years 31-50 years 51-70 years > 70 years AI for Women 19-30 years 31-50 years 51-70 years > 70 years 120 1lg/day of vitamin K 120 1lg/day of vitamin K 120 1lg/day of vitamin K 120 1lg/day of vitamin K 90 1lg/day of vitamin K 90 1lg/day of vitamin K 90 1lg/day of vitamin K 90 1lg/day of vitamin K Pregnancy Method Used to Set the Adequate Intake Data pertaining to vitamin K status of pregnant women are limited but suggest that status is not different from that of nonpregnant women, that is, lack of signs of clinical deficiency and comparable circulating vitamin K concentrations (Manclelbrot et al., 1988; von Kries et al., 1992~. Furthermore, there are no ciata on the vitamin K content of fetal tissue for estimating additional needs during pregnancy.
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From page 183... ...
There was no significant correlation between phylloquinone intake and breast milk concentration. Baseci on NHANES III intake estimates, meclian phylloquinone intakes of 99 lactating women was 74 ~g/ciay, which is
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From page 184... ...
Therefore, the AI is the same as for nonpregnant women. Vitamin KAl Summary, Lactation AI for Lactation 14-18 years 19-30 years 31-50 years 75 1lg/day of vitamin K 90 1lg/day of vitamin K 90 1lg/day of vitamin K INTAKE OF VITAMIN K Food Sources Early ciata obtained by chick bioassay on the vitamin K content of foocis were unreliable and a limited number of foocis were assayoci.
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From page 185... ...
Food and Drug Administration Total Diet Study (Booth et al., 1996b)
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From page 186... ...
Dietary Intake The availability of reliable ciata on the vitamin K content of foocis has now macle it possible to obtain reasonable estimates of the clietary phylloquinone intake of the North American population. The results of a number of studies on phylloquinone intake that used clietary records, with or without recall or a food frequency questionnaire, have been summarized by Booth and Suttie (1998)
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From page 187... ...
TOLERABLE UPPER INTAKE LEVELS The Tolerable Upper Intake Level (UL) is the highest level of ciaily nutrient intake that is likely to pose no risk of adverse health effects for almost all inclivicluals.
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From page 188... ...
Intake Assessment The highest intake of dietary vitamin K reported for the U.S. population was 340 ~g/day in women aged 19 through 30 years (Appenclix Table C-10.
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From page 189... ...
1999. Serum undercarboxylated osteocalcin concentration is reduced by vitamin K supplementation.
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1996a. Dihydro-vitamin K1: Primary food sources and estimated dietary intakes in the American diet.
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1999. Vitamin K intake and hip fractures in women: A prospective study.
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1993. Circulating levels of vitamins K1 and K2 decreased in elderly women with hip fracture.
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1998. Age-related changes in serum undercarboxylated osteocalcin and its relationships with bone density, bone quality, and hip fracture.
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in elderly women. ~ Bone Miner Res 6: 1211 -1216.
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1993. Serum Undercarboxylated osteocalcin is a marker of the risk of hip fracture in elderly women.
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From page 196... ...
von Kries R Kordass U
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