Hypovitaminosis D in adolescents living in the land of sun is correlated with incorrect life style: a survey study in Campania region.

PURPOSE

The aim of this study is to investigate in a population of adolescents living in Regione Campania, undergoing sun exposure at least 9 months per year the prevalence of severe deficiency (<20 ng/ml) or insufficiency (21-29 ng/ml) of 25-Hydroxyvitamin D (25(OH)D) levels and its relationship with individual body weight, use of smoking, and exercise performance.

METHODS

From October 2012 to October 2013, 373 healthy subjects (153 girls, 223 boys 11-20 years) without chronic diseases were consecutively enrolled in a campaign to prevent metabolic, cardiovascular, and oncological diseases. 25(OH)D assay, BMI, and lifestyle habitudes (smoking and exercise indoor or outdoor) were assessed.

RESULTS

In this population, median 25(OH) level was 25.0 ng/ml (95 %CI 23.8-25.2) without any difference between girls (25.0 (95 %CI 23.1-25.7)) and boys (24.3 (95 %CI 23.8-25.2)). Severe deficiency was found in 6 girls (0.02 %), while insufficiency was found in 296 patients (110 girls, 79.3 %). Normal levels were found in 71 patients (37 girls, 19 %). Vitamin D levels were significantly correlated with BMI (r = -0.429, p < 0.0001), smoking (r = -0.241; p < 0.0001), and exercise performance (r = 0.791; p < 0.0001). At the multistep regression analysis, Vitamin D levels were best predicted by exercise performance (t = 19.6, p < 0.0001), less smoking addiction (t = -4.97, p < 0.001), and lower BMI (t = -4.69, p < 0.0001).

CONCLUSIONS

The current study demonstrates that Vitamin D levels are commonly unsatisfactory in adolescents. Lower levels were found in overweight or obese adolescent, smokers and with low or absence of physical activity outdoors.