Only enjoy cooked beans
In 2020, poison centres in Germany received an unexpectedly high number of enquiries about complaints relating to eating green beans. The change in eating behaviour in private households, brought about by the pandemic, could have contributed to this effect. Various studies indicate that people in Germany consume more vegetables and cook at home more often than before the pandemic. "In contrast to many other types of vegetables, beans cannot be eaten raw," says Professor Dr. Dr. Andreas Hensel, President of the Federal Institute for Risk Assessment (BfR). "Raw beans contain phasin. This protein can be harmful to human health even in minimal doses and is only destroyed by high temperatures." The BfR's Assessment of Intoxications Committee therefore advises particular caution. Gentle cooking methods, such as gentle stewing or steaming, are not suitable for beans. Legumes are, however, easily digestible when heated sufficiently. They contain many valuable ingredients.
Link to the BfR app "Poisoning Accidents in Children":
In modern kitchens, light cooking processes are preferred - this keeps vegetables crunchy and fewer vitamins are lost. With some types of vegetables, such as French beans, however, it is essential to ensure that they are sufficiently heated and cooked during preparation. The seeds and pods of the green French bean contain the protein phasin, which is a lectin protein. Lectins are also found in other types of beans. Phasin can cause gastrointestinal disorders.
Abdominal pain and nausea are common even after consumption of a few raw seeds. In severe cases, bloody diarrhoea, fever and low blood pressure can occur. Symptoms usually begin two to three hours after consuming the seeds. Whether symptoms occur and their severities varies greatly from person to person. Children are particularly at risk due to their low body weight.
In case children accidentally eat raw beans or if consumers experience symptoms after insufficient cooking, the BfR recommends contacting a poison centre immediately. Contact details and further information on poisonous plants can be found in the BfR app "Poisoning Accidents among Children".
Anyone who grows beans should educate children about the poisoning hazard - or make sure that they do not have unsupervised access to the plants. Caution is also advised with seed sachets for sowing: Children may find the often colourfully marbled bean seeds particularly attractive.
About the BfR
The German Federal Institute for Risk Assessment (BfR) is a scientifically independent institution within the portfolio of the Federal Ministry of Food and Agriculture (BMEL) in Germany. The BfR advises the Federal Government and the States ('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.