Vitamin K intake and bone mineral density in women and men.
BACKGROUND
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).


OBJECTIVE
We studied cross-sectional associations between self-reported dietary vitamin K intake and BMD of the hip and spine in men and women aged 29-86 y.


METHODS
BMD was measured at the hip and spine in 1112 men and 1479 women (macro x +/- SD age: 59 +/- 9 y) who participated in the Framingham Heart Study (1996-2000). Dietary and supplemental intakes of vitamin K were assessed with the use of a food-frequency questionnaire. Additional covariates included age, body mass index, smoking status, alcohol use, physical activity score, and menopause status and current estrogen use among the women.


RESULTS
Women in the lowest quartile of vitamin K intake (macro x: 70.2 microg/d) had significantly (P < or = 0.005) lower mean (+/- SEM) BMD at the femoral neck (0.854 +/- 0.006 g/cm(2)) and spine (1.140 +/- 0.010 g/cm(2)) than did those in the highest quartile of vitamin K intake (macro x: 309 microg/d): 0.888 +/- 0.006 and 1.190 +/- 0.010 g/cm(2), respectively. These associations remained after potential confounders were controlled for and after stratification by age or supplement use. No significant association was found between dietary vitamin K intake and BMD in men.


CONCLUSIONS
Low dietary vitamin K intake was associated with low BMD in women, consistent with previous reports that low dietary vitamin K intake is associated with an increased risk of hip fracture. In contrast, there was no association between dietary vitamin K intake and BMD in men.
Booth
Sarah L
SL
Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA 02111, USA. sarah.booth@tufts.edu
Broe
Kerry E
KE
Gagnon
David R
DR
Tucker
Katherine L
KL
Hannan
Marian T
MT
McLean
Robert R
RR
Dawson-Hughes
Bess
B
Wilson
Peter W F
PW
Cupples
L Adrienne
LA
Kiel
Douglas P
DP
D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density / Q000187:drug effects* / Q000502:physiology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D019587:Dietary Supplements; D005260:Female; D005272:Femur Neck / Q000033:anatomy & histology / Q000187:drug effects; D006620:Hip Fractures / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D013131:Spine / Q000033:anatomy & histology / Q000187:drug effects; D011795:Surveys and Questionnaires; D014812:Vitamin K / Q000008:administration & dosage*
D014812:Vitamin K