This episode reviews the evolution of vitamin D management frameworks, highlighting the shift from intake based recommendations by the National Academy of Medicine to the 2011 Endocrine Society’s laboratory driven approach, and back to a modern intake focused strategy in the 2024 guideline. The discussion emphasizes when vitamin D testing is appropriate, the role of 25 hydroxyvitamin D in assessing stores, and why routine screening is no longer recommended in healthy individuals. Key clinical takeaways include evidence based supplementation for specific populations such as older adults, pregnancy, and high risk prediabetes, along with a preference for consistent daily dosing over intermittent high dose regimens.