Vitamin E homologues α - and γ-tocopherol are not associated with bone turnover markers or bone mineral density in perimenopausal and postmenopausal women

IntroductionVitamin E has anti-oxidant and -inflammatory properties hypothesized to benefit bone, but limited studies exist regarding its homologues. We examined circulating and dietary α- and γ-tocopherols with bone turnover markers (BTMs) and bone mineral density (BMD), and the role of inflammation in this relationship. MethodsWe performed two cross-sectional analyses from two visits (V2: 1997-1999 n=3883; V3: 2007-2011 n=2130) of the Aberdeen Prospective Osteoporosis Screening Study. Dietary and supplement intake by food frequency questionnaire were assessed at both visits. V2 BTMs (urinary free pyridinoline and deoxypyridinoline, serum N-terminal propeptide of type 1 collagen) and V3 serum α- and γ-tocopherols, inflammatory markers (interleukin-6 [IL-6], serum amyloid A [SAA], high-sensitivity C-reactive protein [hs-CRP], E-selectin), and dual x-ray absorptiometry BMD at the femoral neck and lumbar spine were collected. Food sources of tocopherol homologues and diet-serum correlations were determined. The relationships between dietary tocopherols and BTMs (V2), and dietary and serum tocopherols with BMD (V3) were examined by multivariable regression (adjusting for age, cholesterol, inflammatory markers, carotenoids, body mass index, height, physical activity level, alcohol intake, smoking status, and national deprivation category).ResultsSerum γ-tocopherol was associated with increasing concentrations of hs-CRP, SAA, and E-selectin (P-trend all <0.0001), while α-tocopherol was associated with decreasing concentrations of IL-6 and hs-CRP (P-trend all <0.001). Controlling for covariates, serum α-tocopherol was positively associated with BMD at the femoral neck (β=0.002, P=0.04) among those not reporting vitamin E supplementation. ConclusionWe did not find biologically meaningful results between dietary and tocopherol homologues with BTMs or BMD.