Overview
- Experts reiterated on Wednesday that excessive vitamin D intake usually comes from supplements or fortified products rather than sunlight or normal food and that combined sources can push intake into dangerous ranges.
- Health authorities set the recommended adult intake at about 20 micrograms (800 IU) per day and the European Food Safety Authority caps safe daily intake at 100 micrograms for adults and children 11 and older.
- Longevity specialist Dr. Felix Bertram advised measuring blood vitamin D before long‑term high‑dose use and said he would not recommend more than roughly 2,000 IU per day without a doctor’s supervision.
- Doctors diagnose excess with blood tests for 25‑OH‑vitamin D and calcium, treat mild cases by stopping supplements, and use medications to lower calcium in severe cases to prevent kidney damage and heart rhythm problems.
- Public health data show deficiency is more common than overdose in Germany, so people who have low sun exposure, follow vegan diets, or are older should consider testing and supervised supplementation rather than taking large over‑the‑counter doses.