Vitamin D, genetics, and bone mineral density during weight loss

The current review is to summarize the recent progress in the research of the relation between vitamin D and bone mineral density (BMD) during weight-loss interventions, and describe how genetic factors interact with weight-loss interventions on changes in bone health.

Obesity has shown to be a protective factor for bone health, whereas the relation between weight loss and BMD has yet to be well established. Although beneficial on a variety of metabolic outcomes, weight-loss interventions, such as dietary modifications and surgical treatment, showed adverse effects on bone health in some studies. Despite the biological plausibility for a role of vitamin D in promoting bone health, current evidence does not consistently support the connection between changes in circulating vitamin D levels and BMD during weight loss, partly because of insufficient vitamin D levels during weight loss. Genome-wide association studies have identified genetic variants related to the blood levels of vitamin D; and emerging evidence suggests that dietary intakes may modify the relationship between genetically determined circulating vitamin D levels and change in BMD in response to weight-loss diets.

The relations of changes in circulating vitamin D levels with bone health during weight-loss interventions remain to be established, and the role of genetic factors would be considered in future investigations.