This study examined whether intakes of different dietary fats are associated with alterations of serum 25-hydroxyvitamin D (25OHD) after supplementation with vitamin D(3). 152 healthy men and women age 65 and older were assigned to receive 700 IU/day of vitamin D(3) and 500 mg/d calcium. Intakes of monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), and saturated fatty acids (SFA) were estimated by food frequency questionnaire and changes in plasma 25OHD over 2 years assessed.  The authors found that changes in plasma 25OHD during vitamin D supplementation was positively associated with MUFA, and negatively associated with PUFA.

http://www.ncbi.nlm.nih.gov/pubmed/21816779

Idiopathic osteoporosis (IOP) in premenopausal women is an uncommon disorder of uncertain pathogenesis.  These authors examined the microarchitectural and remodeling features of premenopausal women with IOP. Transiliac biopsies after tetracycline labeling were performed in 104 women: 45 with fragility fractures (IOP), 19 with idiopathic low bone mineral density (Z score ≤-2.0) and 40 controls. Compared with controls, affected women had thinner cortices; fewer, thinner, more widely separated, and heterogeneously distributed trabeculae; reduced stiffness; and lower osteoid width and mean wall width. All parameters were indistinguishable between women with IOP and idiopathic low bone mineral density.  The authors conclude that women with IOP may have high, normal or low bone turnover.  However, those with low bone turnover have the most marked deficits in microarchitecture and stiffness.

http://www.ncbi.nlm.nih.gov/pubmed/21832117