Knowledge and attitudes about vitamin D and sunlight exposure in premenopausal women living in Jeddah, and their relationship with serum vitamin D levels

BACKGROUND: Saudi women are at risk of vitamin D deficiency because they are fully covered by traditional clothing and because of their indoor lifestyle. The latest national study reported that vitamin D deficiency (serum 25(OH)D < 50 nmol/L) affects 72% of young Saudi women. Because little information is available regarding knowledge on vitamin D, attitudes toward sun exposure, and the vitamin D status of premenopausal women in Jeddah, more research is necessary in order to develop effective intervention programs. The purpose of this study is to explore how the relationship between knowledge of vitamin D and attitudes about sun exposure affect the serum 25(OH)D levels in premenopausal Saudi women. METHODS: This cross-sectional study included 257 women aged 20–50 years attending the primary care clinic in Jeddah, Saudi Arabia. Participants completed questionnaires about socio-demographics, dietary vitamin D intake, attitudes toward sun exposure, and were tested on their knowledge of vitamin D. Serum 25(OH)D was evaluated using chemiluminescent microparticle immunoassay. RESULTS: Although 99% of participants had heard of vitamin D and 91% knew that sunlight exposure is a primary source of vitamin D, they also expressed the feeling of having insufficient knowledge regarding vitamin D sources. Furthermore, the majority of participants had negative attitudes toward sun exposure. High fish consumption was associated with a higher level of knowledge regarding vitamin D. The binary logistic regression indicated that low levels of knowledge about vitamin D were associated with low education levels (odds ratio = 0.397, 95% CI = [0.206, 0.765], p = 0.019) and with being married (odds ratio = 0.522, 95% CI = [0.281, 0.971], p = 0.04). In addition, spending time outside in the sun was significantly associated with increased serum 25(OH)D levels (p = 0.006), and the wearing of colored abaya was significantly associated with increased serum 25(OH)D levels (p = 0.008). CONCLUSION: Suboptimal vitamin D status and insufficient knowledge of vitamin D intake sources are common in premenopausal women in Jeddah. Based on this data, health professionals could provide medical intervention to the most vulnerable female patients, as well as offer clear guidelines and information to the general public. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s41043-021-00263-w.