Anise (Pimpinella anisum) has been used for centuries as a flavorful spice and a traditional medicine. However, its purported health benefits can be overshadowed by significant risks for certain people. Understanding these contraindications is crucial for safe consumption, especially when considering anise in medicinal quantities, such as concentrated oils or teas.
Hormone-Sensitive Individuals
Anise contains a compound called anethole, which exhibits estrogen-like properties. For people with hormone-sensitive conditions, this phytoestrogenic effect can be problematic and potentially dangerous. Individuals diagnosed with or at risk for these conditions should avoid anise in all forms, particularly in medicinal dosages.
Examples of hormone-sensitive conditions that may be negatively impacted include:
- Breast cancer
- Uterine cancer
- Ovarian cancer
- Endometriosis
- Uterine fibroids
Pregnant and Breastfeeding Women
The safety of consuming anise in medicinal amounts during pregnancy is not well-established, and some sources even classify it as a reputed abortifacient. For this reason, medical professionals advise pregnant women to err on the side of caution and consume no more than typical food amounts. Similarly, while some cultures use anise to increase milk flow during breastfeeding, there is not enough reliable information to confirm its safety. The estrogen-like effects could potentially cause serious side effects in infants, especially if the tea is contaminated. Therefore, it is best for breastfeeding women to avoid medicinal doses of anise.
Infants and Children
Anise tea is a traditional, but highly dangerous, remedy sometimes used for infant colic. The primary risk comes from the potential for anise products to be contaminated with Japanese star anise (Illicium anisatum), which is virtually indistinguishable from Chinese star anise (Illicium verum) and contains potent neurotoxins. Ingesting this toxic variety can lead to severe side effects in infants and children, including vomiting, irritability, and seizures. The FDA has specifically warned against giving star anise tea to infants. Given the difficulty in ensuring product purity, and the high risk of contamination, anise should be completely avoided for infants and young children.
Individuals with Allergies
As a member of the Apiaceae plant family, anise can cause allergic reactions, especially in those who are allergic to other family members. Symptoms can include skin irritation, respiratory issues, and gastrointestinal upset.
Other plants in the Apiaceae family that may cause cross-reactivity include:
- Celery
- Coriander
- Cumin
- Dill
- Fennel
- Caraway
People on Specific Medications
Anise can interact with a variety of medications, altering their effectiveness. The estrogenic effects of anise are particularly relevant for those on hormone-based therapies.
Significant Drug Interactions
- Hormonal birth control: Large amounts of anise could decrease the effects of contraceptive drugs.
- Estrogen medication: Taking anise alongside estrogen pills may alter their intended effects.
- Tamoxifen (Nolvadex): Anise's effect on estrogen levels might reduce the effectiveness of this breast cancer treatment.
- Diabetes medications: Anise may lower blood sugar levels, increasing the risk of hypoglycemia when combined with anti-diabetes drugs.
- Certain CNS drugs: Anise oil can affect the central nervous system, potentially altering the effects of medications like diazepam (Valium), codeine, fluoxetine (Prozac), and imipramine (Tofranil).
Before and After Surgery
Because anise can influence blood sugar levels, it poses a risk for individuals undergoing surgery. Its effect on blood sugar can interfere with its control during and after the procedure. It is recommended to stop consuming anise at least two weeks prior to any scheduled surgery to mitigate this risk.
Anise vs. Star Anise: A Critical Distinction
While the flavors are similar due to the presence of anethole, anise and star anise come from different plants and have different safety profiles. The biggest danger lies with star anise, particularly the threat of contamination with its toxic Japanese cousin.
| Feature | Anise (Pimpinella anisum) | Star Anise (Illicium verum) |
|---|---|---|
| Botanical Family | Apiaceae (Parsley family) | Schisandraceae (Magnolia family) |
| Appearance | Small, pale brown seeds | Hard, eight-pointed star-shaped pod |
| Primary Risk | Hormone-like effects, medication interactions, and potential allergies | Contamination with highly toxic Japanese star anise (I. anisatum) |
| Infant Safety | Avoid medicinal amounts due to potential hormonal effects | UNSAFE; high risk of neurotoxic contamination |
Conclusion
Although anise is generally safe for consumption in standard culinary amounts, it presents clear and significant risks for specific individuals and circumstances. People with hormone-sensitive cancers, pregnant or breastfeeding women, and infants should strictly avoid it, especially in concentrated medicinal forms. Additionally, caution is advised for individuals with known allergies to related plants, those on certain medications, or anyone preparing for surgery. When using star anise, always ensure it is from a trusted source to prevent accidental consumption of the poisonous Japanese variety. As with any herbal supplement, consulting a healthcare provider is the safest course of action, especially for medicinal use. For more information on potential drug interactions, a reliable resource is available at WebMD: Anise.
