What role does VDR play in skin aging?

VDR (vitamin D receptor) is a nuclear receptor that regulates gene expression in skin cells such as keratinocytes and fibroblasts. Vitamin D binding to VDR influences proliferation, differentiation, apoptosis, and provides photoprotection – all processes relevant to skin aging. However, direct evidence for VDR polymorphisms in skin aging is weak in the provided context. The context only mentions VDR in relation to DNA tests for vitamin D needs in athletes, not specifically skin aging. Mechanistically, the role is plausible, but human studies show small effect sizes and are often ancestry-dependent. Without clinical confirmation (e.g., vitamin D levels, skin biopsies), the predictive value remains limited. Therefore, caution is warranted: VDR gene variants alone are not a strong predictor of skin aging. Evidence: mechanistic, not supported by strong human studies in the given context.