[Prevalence of deficient and insufficient vitamin D levels in a young healthy population].

BACKGROUND AND OBJECTIVES

Recent studies have shown a high frequency of insufficient serum vitamin D levels in the general population, especially in the elderly and in individuals with osteoporosis. Data from the young adult population are scarce, but also reveal a high prevalence of vitamin D insufficiency and deficiency in this age group. The main reasons for this high prevalence seem to be poor dietary vitamin D intake and low sun exposure. The aim of the present study was to determine the prevalence of vitamin D insufficiency and deficiency in a young healthy population and its association with concentrations of calcium and parathyroid hormone and sun exposure.

METHODS

We performed an observational, descriptive study in 116 subjects (38 men and 78 women aged 26.56 +/- 3.32 years), during the late spring and early summer of 2007. Fasting blood samples were obtained and levels of 25-hydroxivitamin D, intact parathyroid hormone, calcium, albumin and creatinine were measured. A questionnaire designed to assess sun exposure and sunshine protection during the previous 12 months was administered.

RESULTS

The mean value of 25-hydroxivitamin D obtained was 24.58 +/- 6.98 ng/ml. The subjects were divided into three groups according to 25-hydroxivitamin D levels: deficient: < 20 ng/ml (27.58%); insufficient: 20-30 ng/ml (56.03%); and sufficient: > or = 30 ng/ml (16.37%). No statistically significant differences were found between the groups or the studied variables except for age in relation to vitamin D levels.

CONCLUSIONS

Our study shows a high prevalence of vitamin D insufficiency in a young healthy population with no clear relationship with sun exposure or sunscreen protection. The low intake of food rich in vitamin D and the lack of food fortification combined with scarce effective sun exposure could account for the low serum levels of vitamin D in this population.