Vitamin D status may contribute to serum insulin-like growth factor I concentrations in healthy subjects

Abstract

Objective: The aim of the study was to evaluate whether vitamin D [25-(OH) D3] status affects serum IGFI concentrations in healthy subjects.

Design and patients: Two hundred and forty-one consecutive healthy subjects were included in the present study.

Measurements: Serum IGF-I and 25-(OH) D3 concentrations.

Results: As expected, serum IGF-I concentrations progressively decreased with age (r=-0.55, p<0.0001); on the contrary, gender was not related to serum IGF-I levels. A positive relationship was identified between serum 25-(OH) D3 and IGF-I concentrations (r=0.33, p<0.0001); the 25-(OH) D3-dependent changes of serum IGF-I concentrations were observed also when subjects were divided on the basis of vitamin D deficiency; in fact, those with severe 25-(OH) D3 deficiency (<20 ng/ml) had lower (185 ± 83 μg/l) IGF-I values than those with mild-to absent 25-(OH) D3 deficit (225 ± 83 μg/l, p=0.0004).

Conclusions: 25-(OH) D3 status may contribute to determine serum IGF-I levels in healthy population.