# Vitamin D health and supplementation requirements > Live situation record from CLSTR: https://clstr.news/situations/vitamin-d-health-and-supplementation-requirements > Updated: 2026-08-24T03:00:00.000Z. Sources: 4. Developments: 2. Vitamin D is identified as a critical component for bone development, immune system function, and neurological health. It facilitates the absorption of calcium and phosphorus, which is essential for preventing conditions such as rickets in children and osteoporosis in adults. Due to the body’s potential inability to produce sufficient levels during winter, supplementation is a common medical recommendation, particularly for infants and children. Medical standards for optimal levels vary; for instance, the Robert Koch Institute suggests a 25(OH)D serum value between 30 and 50 ng/ml, noting that levels below 30 ng/ml are associated with deficiency. Research indicates that effective calcium balance requires more than Vitamin D alone. While Vitamin D aids intestinal calcium absorption, Vitamin K is necessary to direct that calcium toward bone tissue, and Magnesium is required for the enzymatic processes that activate Vitamin D. Without these supporting nutrients, increased Vitamin D intake may not optimize bone outcomes. ## Timeline ### 2026-08-24: Vitamin D importance for bone health and immune function Vitamin D is essential for bone health, immune function, and development. Experts highlight the importance of maintaining optimal serum levels to prevent deficiencies and bone-related diseases. 2 sources. https://clstr.news/cluster/vitamin-d-importance-for-bone-health-and-immune-function ### 2026-08-19: Vitamin D supplementation requires calcium balance with Vitamin K and Magnesium Effective calcium balance and bone health require more than high-dose Vitamin D; Vitamin K and Magnesium are essential for directing calcium to bone tissue and activating Vitamin D. 2 sources. https://clstr.news/cluster/vitamin-d-supplementation-requires-calcium-balance-with-vitamin-k-and-magnesium --- Cite as: Vitamin D health and supplementation requirements. CLSTR, https://clstr.news/situations/vitamin-d-health-and-supplementation-requirements