S L Booth

..Limited data suggest that the relative bioavailability of phylloquinone from vegetables is lower than that from a supplement. This finding is relevant to the maintenance of optimal vitamin K status...

..Vitamin K has been associated with bone mineral density (BMD) and risk of hip fracture. The apolipoprotein (apo) E4 allele (APOE*E4) has been associated with bone fracture through a putative effect on vitamin K transport in blood...

..However, little is known about the effects of hydrogenation on other components, such as vitamin K. Low phylloquinone (vitamin K1) intake is a potential risk factor for bone fracture, although the mechanisms of this are unknown...

..001). These data emphasize that the use of different approaches for the assessment of vitamin K absorption can result in disparate conclusions...

..Despite these caveats, these findings support the use of a FFQ for a relative assessment of vitamin K status in population-based studies...

..The impact of high phylloquinone intake on bone mineral density and fracture risk needs to be ascertained in randomized clinical trials...

..To assess the genetic and nongenetic correlates of circulating measures of vitamins K and D status in a community-based sample of men and women...

..Additional studies are needed to further explore the relationships among body fat, storage of vitamin K in adipose tissue, and implications for vitamin K status and function...

..Vitamin K modulates cytokines involved in bone turnover, including interleukin-6 (IL-6) and osteoprotegerin in vitro...

..Limited evidence suggests that vitamin K may have a beneficial role in glucose homeostasis. No observational data exist on the associations between vitamin K intake and insulin sensitivity...

..However, data are limited on the effects of dietary vitamin K...

..Vitamin K has a potentially beneficial role in insulin resistance, but evidence is limited in humans. We tested the hypothesis that vitamin K supplementation for 36 months will improve insulin resistance in older men and women...

..Thus, fat mass appears to influence serum carotenoid concentrations in only certain subjects (i.e. older women) who have relatively high percentage of body fat...

..Our findings suggest that this animal model may be useful for investigation of the effect of the dietary vitamin K on sulfatide metabolism, myelin structure and behavior functions...

..Higher intakes of cereal fiber, particularly from whole-grain sources, are associated with lower total percent body fat and percent trunk fat mass in older adults...

..To understand the impact of vitamin K nutrition on healthy aging it is necessary to assess both the determinants and the adequacy of vitamin K nutritional status of the elderly...

..There is also an emerging viewpoint that the biochemical function of vitamin K may extend beyond that of a cofactor for the VKD carboxylation of glutamyl residues (Glus) to carboxylated Glus in VKD proteins...

..A preventive role for vitamin K in CAC progression has been proposed on the basis of the properties of matrix Gla protein (MGP) as a vitamin K-dependent calcification inhibitor...

..The observation that high vitamin K status was associated with lower concentrations of inflammatory markers suggests that a possible protective role for vitamin K in inflammation merits further investigation...

..Poor diet may affect bone status by displacing nutrients involved in bone health. Dihydrophylloquinone, a form of vitamin K present in foods made with partially hydrogenated fat, is a potential marker of a low-quality dietary pattern...

..However, there are emerging data that suggest the efficacy of vitamin K supplementation on bone loss is inconclusive...

..Vitamin K has been implicated in bone health, primarily in observational studies. However, little is known about the role of phylloquinone supplementation on prevention of bone loss in men and women...

..The presence of MK-4 in meat, eggs, and dairy foods could be important as physiologic functions unique to MK-4 are identified...

..Dihydrophylloquinone may be used in models for the study of tissue-specific vitamin K deficiency...

..Low dietary vitamin K intake has been associated with an increased risk of hip fracture in men and women. Few data exist on the association between dietary vitamin K intake and bone mineral density (BMD)...

..Moreover, our findings suggest that the current recommended Adequate Intake levels of vitamin K (90 micro g/d) in women do not support maximal osteocalcin gamma-carboxylation in older women...

..Menu planning for patients on warfarin can include a healthy diet including fruits and nuts without compromising the stability of their oral anticoagulation therapy...

..Using this method, urinary menadione was shown to increase in response to 3 years of phylloquinone supplementation. This HPLC method is a sensitive and reproducible way to detect menadione in urine...

..Although a vitamin E-vitamin K interaction was proposed to underlie this effect, it has not been systematically investigated in adults with normal baseline coagulation status...

..While an encouraging option for management of warfarin therapy, longer-term studies in different patient populations are required...

..Clinical trials are required to isolate any putative effects of vitamin K on rates of bone loss. The target population in these trials, particularly in regard to estrogen use, may be critical, as suggested by the findings of this study...

..However, the precise mechanisms of action are not well understood. Further, the physiological consequences of the observed effects of vitamin K on sphingolipid metabolism have not been systematically studied...

..Despite this caveat, higher plasma dihydrophylloquinone was associated with higher dihydrophylloquinone intake and higher trans fatty acid intake...

..002). Vitamin D status may be an important determinant for change in fasting plasma glucose concentration among middle-aged and older adults without diabetes...

..To examine the feasibility of using phylloquinone intake as a marker for coronary heart disease (CHD) and stroke risk in women...

..Vitamin K has bone and cartilage effects, and previously shown to be associated with radiographic osteoarthritis. We evaluated vitamin K's effect on hand osteoarthritis in a randomised controlled trial...

..To develop and validate a brief, self-assessment instrument (K-Card) to determine daily variations in dietary vitamin K1 (phylloquinone) intake for use in patients receiving oral warfarin anticoagulant therapy...

..Polymorphisms in genes encoding enzymes involved in vitamin K metabolism may modulate plasma concentrations of phylloquionone and percent carboxylation of osteocalcin...

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..In vitro and animal studies indicate that high uncarboxylated osteocalcin is associated with reduced insulin resistance. However, associations between osteocalcin and measures of insulin resistance in humans are less clear...

..8 hours (n = 3). Deuterated-phylloquinone was not detectable in plasma or TRL fraction at 72 hours. These results suggest rapid uptake and transport of physiologic doses of phylloquinone...

..The mechanisms by which 9-cis RA and 1,25(OH)(2)D3 alter vitamin K concentrations warrant further investigation...

..We aimed to identify common genetic variants affecting vitamin D concentrations and risk of insufficiency...

..Accumulating evidence suggests that vitamin D is involved in the development of type 2 diabetes (T2D)...

..The results of this study suggest a role for MGP genetic variants in coronary atherosclerosis among men that is not reflected in serum MGP concentrations...

..13). The LC-APCI/MS method is a sensitive technique for simultaneous determination of both unlabeled and labeled phylloquinone and can be applied to bioavailability studies...

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..Compatible with the long-standing concept that fat tissue is a storage site for vitamin D, fat tissue and serum vitamin D(3) concentrations were positively correlated...

..Further evidence is provided for the notion that calcifications in those regions are associated and that MDCT can be used as a tool for the global assessment of vascular and valvular calcium...

..To confirm reports that 25-hydroxyvitamin D (25[OH]D) deficiency is associated with an increased risk of joint space narrowing or cartilage loss in osteoarthritis (OA)...

..Among adults without diabetes, vitamin D status was inversely associated with surrogate fasting measures of insulin resistance. These results suggest that vitamin D status may be an important determinant for type 2 diabetes mellitus...

..This review summarizes current recommendations for vitamin K in rodent diets relative to our evolving knowledge about this fat-soluble vitamin...

..Diet composition is one of the factors that may contribute to intraindividual variability in the anticoagulant response to warfarin...

..The evidence to support this putative role of vitamin K intake in atherosclerosis is reviewed...

..Nondietary determinants of vitamin K status include apolipoprotein E (apoE) genotype, which may influence vitamin K transport to peripheral tissues...

..699, P < 0.001). We conclude that the urinary excretion of vitamin K metabolites reflects dietary phylloquinone intake and offers the first candidate marker of global vitamin K status...

..To determine whether orlistat causes fat-soluble vitamin deficiencies in African-American and Caucasian adolescents...

..Rates of bone Ca deposition were lower than typically reported in healthy children, as were indirect markers of bone formation. These alterations in bone turnover contribute to reduced bone mass in girls with CF...

..A growing body of evidence suggests that vitamin D deficiency may adversely affect the cardiovascular system, but data from longitudinal studies are lacking...

..Matrix Gla protein (MGP) is an inhibitor of calcification in vivo. However, little is known regarding the distribution of circulating MGP and its associations with CHD risk factors or with CAC in humans...

..Genome-wide association studies (GWAS) provide mechanisms to investigate the genetic contributions to biomarker variability unconstrained by current knowledge of physiological relations...