Vitamin D Insufficiency Strongly Associated With Obesity Vitamin D Status and Its Relationship to Body Fat, Final Height, and Peak Bone Mass in Young Women

Objective: To determine the relationship of Vitamin D levels with anthropometric measurements at time of peak bone mass. Design/Methods: This was a cross-sectional study involving 90 post-pubertal females between the ages of 16 and 22 years who had bone and fat measurements performed using DEXA scan and computerized tomography, as well as biochemical determinations of 25-hydroxyvitamin D2 and D3, and parathormone assays. This was a multi-ethnic and multi-racial population. The results of this study are eye opening. Results: There was significant positive correlation between height and 25OHD levels, and conversely significant negative correlations between vitamin D levels, weight, and body mass index irrespective of ethnic background. There was a significant inverse correlation between 25-hydroxyvitamin D and parathormone. Parathormone levels were higher in the vitamin D-insufficient rather than the vitamin D-sufficient group. Conclusions: Vitamin D insufficiency is not associated with ethnic or racial variation. Vitamin D insufficiency is associated with increased body fat and decreased height, but not changes in peak bone mass. Reviewer's Comments: Strangely, this study did not demonstrate a correlation between vitamin D status and bone mass determination. Previous studies of adolescents have been inconsistent in this regard. What this study does show is that vitamin D insufficiency is extremely common in young women--59% in this population--and is correlated with obesity, likewise very common in this population, as well as height. Here is a study in a sun-rich area of the United States showing a high prevalence of adolescent vitamin D insufficiency, of which body fat may be a contributor, or perhaps vitamin D insufficiency is a risk factor for obesity. Hmmmm....