Why fennel tea can be dangerous for babies and toddlers

Is your breastfeeding baby suffering from stomach ache? Drink fennel tea. Does your baby have wind? Give him fennel tea. Does your toddler have a cold? Give him fennel tea. It's no wonder that this household remedy has a permanent place in the kitchen cupboard of every family with children: Fennel is not only said to have antispasmodic and expectorant properties. Unlike other varieties, it can also be given to babies in tea form. At least that has always been the general assumption.

Now, however, this traditional remedy is falling into disrepute. The reason: fennel contains estragole - and this natural substance can be harmful. The latest studies indicate that it is harmful to health in high quantities. Mice and rats that were given high concentrations of estragole were more likely to develop liver cancer than those that were not given estragole.

Exact estragole dosage is not possible

It is not yet clear how great the effects are for humans. Nevertheless, various authorities have already issued warnings. First the European Medicines Agency in May last year. Just under a year later, Swissmedic has now followed suit.

The Swiss regulatory and supervisory authority for medicinal products and medical devices recommends that children under the age of four should only be given fennel tea in consultation with a healthcare professional. And even to avoid it altogether during pregnancy and breastfeeding.

The problem with fennel tea is that it is not possible to determine the exact dosage of estragole, according to the official letter from March. "Factors such as the temperature and quantity of water or the duration of steeping influence the quantity of ingredients that are released and thus consumed." Swissmedic is in contact with the marketing authorisation holders, it continues. If necessary, further measures will be taken, such as amending the package leaflet for the corresponding medicinal products.

However, teas containing fennel are not always a medicinal product. You can find them on the tea shelves of wholesalers like any other variety, and they are also available from Galaxus in the tea range. Sold as foodstuffs, they fall under the jurisdiction of the Federal Veterinary and Food Safety Office. In response to an enquiry from SRF, it stated: "The tolerable daily intake of the substance estragole is not known." The scientific work on fennel and estragole by the European Food Safety Authority is being followed and "a decision will be made on possible measures based on the results".

There are alternatives

Jakob Maske, paediatrician and spokesperson for the German Professional Association of Paediatricians, told MDR: "Fennel is always said to have a healing effect. This has never really been proven." In the past, people simply never opposed fennel tea, "we would do that now". The teas contain such different concentrations of estragole that you can actually reach a high daily dose with normal amounts.

Peter Voitl from the Medical University and the Sigmund Freud Private University in Vienna says something similar. The estragole content in fennel teas varies greatly. "Considering that fennel is also contained in some baby foods, the actual or achievable daily dose remains uncertain and could possibly reach the hepatotoxic range."

Until this has been fully clarified, pregnant women, breastfeeding mothers and children under the age of four would be well advised to avoid fennel-containing (breastfeeding) teas. And fall back on alternatives - but do they even exist? Christian Braegger, President of the Swiss Paediatricians' Association, recommends chamomile or rose hip tea to SRF. The Swiss Midwives Association, which drew attention to the fennel tea issue even before the Swissmedic safety warning, says: "It is best for breastfeeding women to seek advice from a drugstore or pharmacy and mix a breastfeeding tea that does not contain fennel," says President Barbara Stocker Kalberer. <p