An Alarming High Prevalence of Vitamin D Deficiency Among Healthy Adults

Background and objectives: Vitamin D is critically important for the development, growth and maintenance of healthy bones from birth to death. This research is designed to study the prevalence of vitamin D deficiency among healthy adults, and to assess the demographic features, sunlight exposure, dietary habits and other risk factors. Methods: A cross sectional study including 365 subjects above the age of 18 years, randomly selected from five healthy care (early case detection) clinics. The study was conducted from April to October 2012. Participants completed detailed questionnaires regarding their demographic data, average daily sunlight exposure, dietary habits, multivitamins use and regular exercise. Height and Body mass index (BMI) and circulating levels of 25-hydroxyvitamin D [25(OH) D] were measured. Results: A total of 365 eligible participants included in the study, 25.2% were deficient and 36.2% were insufficient in vitamin D level. Vitamin D deficiency and insufficiency were significantly more frequent among female and age group 60 years and more (p<0.05). After adjustment of age and gender, a highly significant association was found between duration of exposure to sunlight and vitamin D deficiency. The risk to develop vitamin D deficiency is nearly 5 times more in participants exposed to sunlight less than 5 Minutes/Day, when compared with participants exposed to sunlight >30 minutes/Day, OR=5.13 (95% CI=3.14-7.90). Consumption of vitamin D rich food, occupation, BMI and exercise were found to be strong predictors of vitamin D deficiency, OR=4.38, 2.88, 2.46 & 2.74 respectively. Multivitamins use was significantly associated with vitamin D deficiency in univariate analysis (p<0.05), but this was weakened somehow when adjusted in multivariate analysis, adjusted OR=1.17 (95% CI=0.74-2.55). Conclusion & Recommendations: Interventions should be taken to increase consumption of vitamin D rich foods such as fortified milk, fish, liver and cheese, taking a vitamin D supplement, physical exercises, increasing sun exposure to the extent needed for adequate vitamin D production and/or periodic medical examination of healthy adults for early case detection and intervention.