Overview
- Öko-Test tested 28 magnesium-only supplements and found about half exceeded the Bundesinstitut für Risikobewertung’s 250 mg daily reference, a result published on May 28, 2026 that highlights routine overdosage in the market.
- All tested products were judged 'unnecessary' and ranked by concern into three color bands: six yellow, 13 light red and nine dark red based on dose, additives and other defects.
- Many products contained unwanted ingredients such as synthetic sweeteners, binders and emulsifiers that Öko-Test links to possible negative effects on gut microbes and blood-sugar control.
- Health bodies say healthy people with a balanced diet generally do not need supplements and warn excess magnesium can cause diarrhea at around 300 mg per day and serious harm for people with impaired kidney function, so medical advice is recommended before use.
- The market shows wide price and product variation, with daily doses costing €0.02–€1.25 and products aimed at athletes, pregnant women and seniors, which may prompt consumers and regulators to demand clearer labeling and safer dose limits.