Samira Faraji - Student Research Committee, Urmia University of Medical Sciences, Urmia, Iran
Samira Faraji - Department of Human Nutrition, Urmia University of Medical Sciences, Urmia, Iran
Mohammad Alizadeh - Department of Human Nutrition, Food and Beverages Safety Research Center, Urmia University of Medical Sciences, Urmia, Iran

The prevalence of Metabolic Syndrome (MetS) and Vitamin D deficiency are increasing dramatically in the world. The purpose of this review was to survey the recent advances in the field of vitamin D on risk factors of MetS based on existing evidence. In this review, we tried to organize and clarify the existing evidence from randomized controlled trial studies concerning to the effect of vitamin D supplementation on MetS patients. The present study is a review study using randomized controlled trials, full-text English language studies conducted over the last nineteen years (2000–2019) at databases such as Pub Med, Science Direct and Scopus. The present review focuses on the clinical effects of vitamin D consumption on MetS. The nine articles extracted from studies regarding the effect of vitamin D supplementation on MetS were reviewed. Several studies have shown, there is a beneficial effect of vitamin D on MetS, while others have shown no effect. Our review did not show promising results in improving the most risk factors of MetS. However available data from intervention studies are not enough to draw final conclusions on the effect of vitamin D supplementation on risk factors of MetS. Thus new clinical studies are needed to test the hypothesis that hypovitaminosis D worsens risk factors of MetS and correction would alleviate it.

Metabolic Syndrome, Vitamin D, Obesity, Hypertension