How to prepare for Vitamin D Training

The question 'How to prepare for Vitamin D Training' is ambiguous. It likely refers to optimizing vitamin D status before a blood test or starting supplementation. The gold standard is a 25-hydroxyvitamin D blood test. Levels below 30 ng/mL are considered suboptimal. No special preparation is needed for the test, but any supplement intake should be noted. For supplementation, a starting dose of 800–2000 IU/day is common, adjusted based on baseline levels, body weight, and sun exposure. Genetic variants (e.g., in VDR, GC) can modestly affect vitamin D metabolism, but their impact is small and does not warrant routine genetic testing. Evidence for benefit in deficiency is strong (human-strong), while for prevention in healthy individuals it is moderate. Caution: long-term intake above 4000 IU/day may cause hypercalcemia. Medical supervision is advised for high doses. The term 'training' is misleading – it is about supplementation, not physical exercise.