In brief: Fennel seeds come from Foeniculum vulgare and are used in bread, spice blends and herbal teas.
Use and safety
| Topic | Interpretation |
|---|---|
| Culinary spice | Traditional use |
| Tea | Traditional use |
| Estragole | Genotoxic and carcinogenic properties |
| Vulnerable groups | Extra caution in children and pregnancy |
In a 2025 risk assessment, EFSA could not establish a safe exposure level for estragole from fennel-seed preparations and highlighted vulnerable groups.[1]
FAQ
Is fennel tea always harmless?
No.
What is estragole?
A naturally occurring aromatic compound in fennel and other plants.
Are small culinary amounts the same as concentrated tea?
No.
Is fennel-seed oil the same as seeds?
No, essential oil is much more concentrated.
Conclusion
Fennel seeds remain a classic spice. Concentrated and frequent preparations deserve more caution because of estragole.