[Influence of sun exposure and diet to the nutritional status of vitamin D in adolescent Spanish women: the five countries study (OPTIFORD Project)].

INTRODUCTION

Vitamin D deficiency is a big public health concern, especially among women. For this reason, "The Five Countries Study" was set up within the OPTIFORD project. This study aims at knowing the vitamin D status in adolescent and older women in five European countries according to their different dietary and behavioral habits.

OBJECTIVES

To analyze the relative contribution of sun exposure and the diet to the vitamin D status among 47 Spanish adolescents participating in "The Five Countries Study".

METHODS

Validated and standardized questionnaires (health, lifestyle, sun exposure, and frequency of food consumption), biochemical analysis (25-hydroxyvitamin D (S-25-OHD) and parathormone), and assessment of sun exposure (UV dosimeter).

RESULTS

Serum levels of S-25-OHD were higher during the summertime than in winter (61.55±12.85 nmol/l and 45.81±9.29 nmol/l, respectively). Forty-five percent of the sample had a worsening of their vitamin status in the winter, as compared with the summer (p<0.0001). During the summer, vitamin D insufficiency (S-25-OHD≤50 nmol/l) affected 17% of the population, going up to 63% in the winter. Sixty-six percent of the sample did not reach the IR of vitamin D (5 g/day), being the fish the main dietary source of vitamin D.

CONCLUSIONS

Only 34% of the participants had an adequate vitamin D status. Both adequate sun exposure and vitamin D dietary intake are recommended in order to correct deficient and insufficient situations.