NutriVouch
Confidence level
Strong evidence
786 studies

Vitamin D

Last reviewed: 3/2/2026

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Absorption
Take with a fat-containing meal for best absorption. Vitamin K2 improves vitamin D utilization.
Daily Dose
Common dose: 1,000–2,000 IU daily
RDA: 15 mcg (600 IU)
Upper limit: 100 mcg (4,000 IU)
Best form: D3 (cholecalciferol) preferred over D2
Timing: With a fat-containing meal.
Higher doses may be needed for deficiency. Blood testing recommended before megadosing.
Food Sources
  • Salmon570 IU per 100g
  • Egg yolks44 IU per yolk
  • Fortified milk120 IU per cup

Not medical advice