vitamin D deficiency constitutes a major public health problem worldwide. It is estimated that 20% to 80% of American, European, and Canadian are suffering from vitamin D deficiency. Vitamin D gains its importance in the public health from the fact that it is essential for bone health. In aIDition, it has been found to be associated with wide variety of diseases such as diabetes, cardiovascular diseases, and cancers as well as infectious diseases. To assess vitamin D status, 25(OH) D is considered the most accurate way. Different cut off values for vitamin D deficiency are available. However, many researchers suggested that levels of 25(OH) D of <50 nmol/l should be defined as deficiency. In Saudi Arabia high prevalence of vitamin D deficiency has been observed. However no national figure has been made available. It is for this reason that this study aims to systematically review all existing research studies on vitamin D status in the Saudi Arabian population. This will provide a synopsis of Saudi Arabian Vitamin D status, the risk factors that lead to its deficiency. The outcome generated from this study would help in implementing useful public health measures to augment Vitamin D level among the population.

Methodology: Electronic literature search databases, including PubMed and Embase, were used to identify all relevant articles on vitamin D deficiency in Saudi Arabia conducted at any time period. Data on study characteristics, demographic characteristics, as well as outcome measure were extracted from the included studies onto predesigned data extraction sheet. All included studies in this review were assesses for their methodological quality using the John Bridge Institute critical appraisal tool for prevalence studies. Studies that reported the proportion of participants with vitamin D level below 50 nmol/l and 25 nmol/l were included in the Meta analysis. I²  test were conducted to measure the extent of heterogeneity between studies.

Results: a total of 33 studies were included in the final descriptive analysis. However, only data from 15 (n=9812) and 8 studies (n= 16752) were used to calculate the overall proportion of vitamin D level below 50 and 25 nmol/l respectively. The I² test revealed high level of heterogeneity between studies; therefore random effect model was used to compute the overall prevalence.