Risks and limits of Vitamin D Ernährung

The provided context does not directly address risks or limits of vitamin D nutrition. The only hit (VDR rs731236) is a vitamin D receptor variant with GWAS evidence for bone health, but no nutritional or toxicity data. General knowledge: Vitamin D is fat-soluble, so excessive supplementation carries a risk of hypercalcemia (kidney stones, vascular calcification). The tolerable upper intake level is 100 µg (4000 IU) daily for adults, though individual sensitivity varies. Deficiency is common, especially in northern latitudes. Evidence for many health claims (immunity, cancer prevention) is mixed and often based on observational studies. A single VDR SNP is insufficient to assess personal risk or requirement. Blood level testing (25-OH vitamin D) is more informative than genetic analysis. The cited sources do not support specific risks or limits of vitamin D nutrition.