Vitamin D as a multisystem regulatory hormone: Molecular pathways, physiological integration, and implications for...

Area of Science:

• Endocrinology
• Metabolic Science
• Nutritional Science

Background:

• Vitamin D is a secosteroid hormone with widespread physiological roles.
• Deficiency is common and has multisystem implications, leading to increased screening.
• Adverse effects of excessive vitamin D are recognized but less clinically focused than deficiency.

Purpose of the Study:

• To review vitamin D metabolism, physiological roles, and effects of deficiency and excess.
• To provide a systems-level framework linking vitamin D signaling to health outcomes.
• To emphasize mechanistic integration across organ systems.

Main Methods:

• Literature review synthesizing current evidence on vitamin D.
• Focus on molecular pathways and systemic effects.
• Integration of findings across endocrine, musculoskeletal, immune, metabolic, and neurobiological functions.

Main Results:

• Vitamin D regulates multiple organ systems and signaling pathways.
• Altered vitamin D status (deficiency and excess) has significant systemic effects.
• Vitamin D signaling impacts metabolic efficiency, mitochondrial function, and musculoskeletal health.

Conclusions:

• Optimal vitamin D status is vital for metabolic efficiency, mitochondrial function, and musculoskeletal health.
• These mechanisms are directly relevant to exercise performance, recovery, and injury risk.
• Maintaining adequate vitamin D is important for athletic and physically active populations.