title: Phylloquinone Intakes and Food Sources and Vitamin K Status in a Nationally Representative Sample of Irish Adults.
abstract: BACKGROUND
  Data from a nationally representative sample of 18- to 64-y-old Irish adults conducted in 1999 highlighted low phylloquinone intakes. That survey, however, did not include older adults (aged ≥65 y), a subgroup that is potentially at higher risk of low phylloquinone intakes, or a biomarker of vitamin K status.
  
  
  OBJECTIVE
  The objectives of this work were to measure the phylloquinone intake and its adequacy and the serum percentage of undercarboxylated osteocalcin (%ucOC), a vitamin K status biomarker, in a nationally representative sample of Irish adults aged 18-90 y, and to compare these newer data on dietary phylloquinone in adults aged 18-64 y with those from the previous survey.
  
  
  METHODS
  Data and biobanked serum samples from the National Adult Nutrition Survey, a randomly selected sample of Irish adults aged 18-90 y (N = 1500), were accessed. Phylloquinone intakes were estimated from 4-d food diary data and were compared across age groups (18-35, 36-50, 51-64, and ≥65 y). Serum %ucOC was assessed by immunoassay (n = 692).
  
  
  RESULTS
  The mean ± SD intake of phylloquinone from all sources was 85.2 ± 59.1 μg/d, 99% of which was derived from food. Phylloquinone intakes and serum %ucOC were significantly (P < 0.05) lower (14-25%) and higher (27-39%), respectively, in the 18- to 35-y age group than in the 36- to 50-y, 51- to 64-y, and ≥65-y age groups (no differences between these 3 groups; P > 0.2 in all cases). Mean phylloquinone intakes had increased (P < 0.01) modestly (6 μg/d) in 18-64-y-olds across a decade. Of the total study population, 55% had phylloquinone intakes below the United Kingdom recommended intake of 1 μg ⋅ kg body weight-1⋅ d-1CONCLUSION: Our study shows that younger adults (aged 18-35 y) appear to be at higher risk of inadequate vitamin K intake and lower vitamin K status, the health implications of which are unclear and warrant further investigation.
authors.affiliation: Cork Centre for Vitamin D and Nutrition Research.
authors.forename: Aoife
authors.initials: A
authors.lastname: Hayes
authors.affiliation: Cork Centre for Vitamin D and Nutrition Research.
authors.forename: Áine
authors.initials: Á
authors.lastname: Hennessy
authors.affiliation: National Dietary Surveys Research Group, School of Food and Nutritional Sciences.
authors.forename: Janette
authors.initials: J
authors.lastname: Walton
authors.affiliation: Institute of Food and Health, University College Dublin, Dublin, Ireland.
authors.forename: Breige A
authors.initials: BA
authors.lastname: McNulty
authors.affiliation: Cork Centre for Vitamin D and Nutrition Research.
authors.forename: Alice J
authors.initials: AJ
authors.lastname: Lucey
authors.affiliation: Cork Centre for Vitamin D and Nutrition Research.|Irish Centre for Fetal and Neonatal Translational Research, University College Cork, Cork, Ireland; and.
authors.forename: Máiréad
authors.initials: M
authors.lastname: Kiely
authors.affiliation: National Dietary Surveys Research Group, School of Food and Nutritional Sciences.
authors.forename: Albert
authors.initials: A
authors.lastname: Flynn
authors.affiliation: Cork Centre for Vitamin D and Nutrition Research, k.cashman@ucc.ie.|Department of Medicine, and.
authors.forename: Kevin D
authors.identifier: http://orcid.org/0000-0002-8185-1039
authors.initials: KD
authors.lastname: Cashman
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers; D015930:Diet Records; D004034:Diet Surveys; D005260:Female; D005504:Food Analysis; D006801:Humans; D008297:Male; D008875:Middle Aged; D009751:Nutritional Requirements; D010837:Vitamin K 1 / Q000008:administration & dosage* / Q000097:blood*; D055815:Young Adult
chemical_list: D015415:Biomarkers; D010837:Vitamin K 1
keywords: Ireland; food consumption survey; phylloquinone intake; temporal trend; undercarboxylated osteocalcin; vitamin K status