Overview
- Stiftung Warentest examined 25 over-the-counter products and found most were too highly dosed, recommending only GSE Vitamin D compact (200 IU) and Rotkäppchen Vital Vitamin D (400 IU), while five were deemed not suitable.
- Consumers are urged to choose low-dose options in line with the BfR’s cap of 20 micrograms (800 IU) per day for supplements.
- Health bodies advise confirming deficiency with a blood test and note that many adults are already adequately supplied, reserving supplementation for older people, those with little sun exposure, obesity, or specific chronic diseases.
- Chronic high intake can cause hypercalcaemia and kidney damage, with documented hospitalizations and rare deaths in case reports underscoring the risks.
- Depot or very high single-dose regimens and combination products drew criticism for dosing errors and lack of proven added benefit, and some products’ measured contents diverged from their labels.