Abstract
The coronavirus 2019 (COVID-19) pandemic has globally impacted all aspects of life since its emergence and spread. There is a strong biological assumption and progressing epidemiological data supporting the role of vitamin D (VD) in COVID-19 infection. This study aims to determine the knowledge about VD supplements to boost immunity against COVID-19 and if participation in specific behaviors has increased the consumption of VD supplements during social distance restriction in Saudi Arabia (SA) in May 2021. This cross-sectional study used a structured online questionnaire for 2369 SA people, including demographic characteristics and knowledge about VD supplements to boost immunity against COVID-19 showed that there was a significant association between sex and vitamin D deficiency (VDD) (P = .000), and having VDD was strongly associated with having another vitamin deficiency (P = .008). Additionally, there was a statistically significant difference between VDD and cardiovascular (P = .027) and respiratory diseases (P = .019). Almost half of the participants used VD supplements to reduce or heal their COVID-19 symptoms. The adverse association between having VDD and understanding of COVID-19 symptoms was statistically significant (P = .01). Ginger is commonly used as an alternative medicine for the treatment of VD. The administration of VD is now known to be of physiological significance for general health, and evidence suggesting the beneficial role of VD in the prevention and/or treatment of diseases, particularly infectious diseases, such as COVID-19, is increasing.