25-Hydroxyvitamin D3 metabolism modulates the effect of variable UV exposure on 25-hydroxyvitamin D3 plasma concentrations

The kinetics of 25(OH)D₃ synthesis and degradation modulate the effect of variable UV exposure on 25(OH)D₃ concentrations. This results in a regulated plasma signal reflecting local seasonal parameters. While absolute 25(OH)D₃ concentrations are commonly investigated, future studies should also examine their temporal dynamics as a biological signal.