Vitamin D: Why Deficiency Is Common—and Supplementation Often Falls Short

Vitamin D deficiency is often treated as a simple intake problem, yet many people remain deficient despite sun exposure or supplementation. This article explains why vitamin D functions as a hormone-like regulator, how absorption, cofactors, inflammation, and cellular signaling affect outcomes, and why normal blood levels don’t always reflect biological function.

Functional medicine, NutritionMartina SturmApril 10, 2022Denver Sports and Holistic Medicinevitamin D deficiency, functional medicine, nutrient absorption, magnesium deficiency, vitamin D labs, inflammation and immunity, metabolic health, hormone regulation