Glucosamine in food supplements: risky also for patients taking coumarin anticoagulants
Various health claims are used to market food supplements with the ingredient glucosamine in Germany and in the European Union. Thus according to the manufacturers, such products are said to help preserve the flexibility of joints. The Federal Institute for Risk Assessment (BfR) has pointed out that these products not only carry health risks for for persons who take coumarin anticoagulants to inhibit blood clotting. The European Food Safety Authority (EFSA) has now confirmed this assessment by the BfR. "Food supplements containing glucosamine also pose a health risk for patients taking coumarin anticoagulants", says BfR President Professor Dr. Dr. Andreas Hensel. "Glucosamine can amplify the anti-blood clotting effects of drugs and thus lead to haemorrhages."
Glucosamine is an amino sugar which is used in the treatment of knee osteoarthrosis. In addition, glucosamine is used in food supplements in quantities that are too low to have a pharmacological effect. Legally, food supplements are defined as food. Already in 2007 and 2010, the BfR drew attention to the health risks associated with food supplements containing glucosamine. In its opinions, the BfR has notably identified patients who take coumarin anticoagulants to inhibit blood clotting as a risk group.
Having again conducted research on the risks posed by glucosamine as a food ingredient, the EFSA has recently confirmed the assessment by the BfR: in agreement with the BfR’s assessment, the European Food Safety Authority comes to the conclusion that there is evidence for the risk of interaction between glucosamine and coumarin anticoagulants. Glucosamine can boost the anti-blood clotting effects of these drugs, i.e. these effects can suddenly be stronger than expected. One possible consequence are haemorrhages. In the majority of reported cases, the increases detected were symptomless changes in laboratory values. In some cases, however, haemorrhages did occur in various organs, in one case with the consequence of a severe cerebral haemorrhage.
Over the last few years, the EFSA has also investigated the health claims of glucosamine in accordance with the so-called health claims regulation of the EU. In the expert opinions published so far on several submitted health claims for glucosamine as a food ingredient, the authority notes that no sufficient scientific evidence for its efficacy for the use in the healthy general population has been presented. According to both German and European regulations, food must not be marketed using misleading claims.
About the BfR
The Federal Institute for Risk Assessment (BfR) is a scientific institution within the portfolio of the Federal Ministry of Food, Agriculture and Consumer Protection (BMELV). It advises the Federal Government and Federal Laender on questions of food, chemical and product safety. The BfR conducts its own research on topics that are closely linked to its assessment tasks.