Evaluating The Association of Knowledge and Serum Levels in Vitamin D Consumers: A Cross-Sectional Survey During the COVID-19 Pandemic, 2020-2021

Vitamin D deficiency is more prevalent in Iran, making the rational use of it more critical. To this end, assessing people’s knowledge about the rational use of vitamin D and its safety is worthwhile to pursue. Objectives: This study aims to evaluate the level of consumers’ knowledge about vitamin D and its relationship with serum levels. Methods: This is a cross-sectional survey designed to assess consumers’ knowledge and its association with demographic characteristics and their serum 25-hydroxy vitamin D3 (25(OH)D) levels in community pharmacies. The association between demographic parameters, lifestyle, habits, and serum levels was reported. Results: 384 individuals participated in this study, among whom 345 (89.8%) consumers requested large doses of vitamin D3. The average knowledge score was 23.67 ± 7.76 out of 50. The average serum level of 25(OH)D was reported as 49.01 ± 32.01 ng/ml, resulting in 117 (30.5%) subjects were in the "insufficient" levels, 223 (58.1%) were in the "sufficient”, and 44 (11.5%) were in the "hypervitaminosis" levels. There is a significant inverse association between knowledge and age, weight, body mass index, education levels, serum level, and monthly dose. Also, a significant inverse association was detected between knowledge in terms of toxicity and vitamin D level. Further, participants’ knowledge of "hypervitaminosis" was lower than those with "sufficient" levels. Conclusion: Although almost all consumers had a sufficient level of 25(OH)D, the lack of knowledge about vitamin D was evident. It could lead the people being exposed to hypervitaminosis, as were seen in 11.5% of the participants.<p>Background: Vitamin D deficiency is more prevalent in Iran, making the rational use of it more critical. To this end, assessing people’s knowledge about the rational use of vitamin D and its safety is worthwhile to pursue. Objectives: This study aims to evaluate the level of consumers’ knowledge about vitamin D and its relationship with serum levels. Methods: This is a cross-sectional survey designed to assess consumers’ knowledge and its association with demographic characteristics and their serum 25-hydroxy vitamin D3 (25(OH)D) levels in community pharmacies. The association between demographic parameters, lifestyle, habits, and serum levels was reported. Results: 384 individuals participated in this study, among whom 345 (89.8%) consumers requested large doses of vitamin D3. The average knowledge score was 23.67 ± 7.76 out of 50. The average serum level of 25(OH)D was reported as 49.01 ± 32.01 ng/ml, resulting in 117 (30.5%) subjects were in the "insufficient" levels, 223 (58.1%) were in the "sufficient”, and 44 (11.5%) were in the "hypervitaminosis" levels. There is a significant inverse association between knowledge and age, weight, body mass index, education levels, serum level, and monthly dose. Also, a significant inverse association was detected between knowledge in terms of toxicity and vitamin D level. Further, participants’ knowledge of "hypervitaminosis" was lower than those with "sufficient" levels. Conclusion: Although almost all consumers had a sufficient level of 25(OH)D, the lack of knowledge about vitamin D was evident. It could lead the people being exposed to hypervitaminosis, as were seen in 11.5% of the participants.</p>