A meta-analysis of the relationship between vitamin D deficiency and obesity

Abstract

Previous epidemiologic studies suggested that vitamin D deficiency may be a risk factor of obesity. However, the result is still controversial. This meta-analysis aims to provide a comprehensive summary on the association between vitamin D deficiency and obesity. We systematically searched Pubmed database, Chinese Wanfang Data Knowledge Service Platform, and Chinese National Knowledge Infrastructure (CNKI), for the literatures on the relationship between vitamin D deficiency and obesity published from 2010 to 2015. The effect sizes of overall odds ratio (OR) and 95% confidence interval (CI) were estimated using Stata 11.0. Heterogeneity was evaluated using random-effects model and forest plots. Fifteen studies were eligible for inclusion in the meta-analysis, which included 3867 subjects with obesity and 9342 health subjects. Meta-analysis results showed that the prevalence of vitamin D deficiency was difference between obesity group and control group, and the pooled OR (95% CI) was 3.43 (2.33-5.06). The prevalence of vitamin D deficiency was associated with obesity in Asians and European-American, OR (95% CI) were 3.70 (1.98-6.90) and 3.09 (1.89-5.04), respectively. No publication bias was found in our study. vitamin D deficiency may be associated with obesity, irrespective of areas.

Keywords: Vitamin D; meta-analysis; obesity.

Figures

Figure 1

Flowchart of study selection for the association of vitamin D and obesity.

Figure 2

Forest plot for association between vitamin D deficiency and obesity.

Figure 3

Forest plot for association between vitamin D deficiency and obesity in Asians.

Figure 4

Forest plot for association between vitamin D deficiency and obesity in European-American.

Figure 5

Funnel plot for association between vitamin D deficiency and obesity.

Figure 6

Sensitivity analyses for association between vitamin D deficiency and obesity.