Star anise tea is a warm, licorice-flavored drink traditionally used to ease digestive discomfort, support respiratory health, and fight infections. The dried, star-shaped pods of the spice contain several compounds with demonstrated antibacterial, antifungal, anti-inflammatory, and antioxidant properties. While some of these benefits are well-supported by lab research, others remain rooted more in traditional use than clinical proof.
Key Compounds in Star Anise
Star anise (the Chinese variety, Illicium verum) gets its health properties from two standout compounds: anethole and shikimic acid. Anethole is the compound responsible for the strong licorice flavor, and it carries antibacterial, antifungal, and anti-inflammatory effects. Shikimic acid is perhaps the more famous of the two. It serves as the key starting material for manufacturing oseltamivir, the antiviral drug sold as Tamiflu. Much of the world’s shikimic acid supply still comes from Chinese star anise seeds.
Beyond these two, the essential oil extracted from the pods contains smaller amounts of other active compounds, including estragole and linalool, each contributing to the spice’s broad antimicrobial profile.
Digestive Comfort
The most common reason people brew star anise tea is to settle an upset stomach. Star anise has long been classified as a carminative, meaning it helps reduce gas and bloating. Anethole appears to relax smooth muscle in the digestive tract, which can relieve cramping and that uncomfortable “too full” feeling after a heavy meal. In traditional Chinese and Ayurvedic medicine, star anise has been used for centuries specifically for this purpose, and it remains one of the better-supported traditional uses of the spice.
If you’re brewing it for digestion, a simple cup made by steeping one or two whole star anise pods in boiling water for 10 to 15 minutes is the standard approach.
Antimicrobial and Antifungal Effects
Star anise shows broad-spectrum activity against several types of bacteria and fungi in laboratory studies. Its compounds effectively inhibit food-spoilage fungi like Aspergillus and Fusarium species. Research published in Food Research International found that trans-anethole and estragole both demonstrated antifungal activity against Penicillium roqueforti and Aspergillus niger, two common molds. Linalool, another component, showed activity specifically against Aspergillus niger.
These findings are from lab settings, not from people drinking the tea. The concentrations used in petri dishes are typically higher than what you’d get from a cup of star anise tea. Still, the antimicrobial profile helps explain why star anise has been a go-to folk remedy for mild infections and sore throats across many cultures.
Respiratory Health
Star anise tea is widely used as a home remedy for coughs, bronchitis, and nasal congestion. People have traditionally relied on it as an expectorant, meaning it may help loosen mucus in the airways. Some people also inhale the steam from the brewed tea to ease congestion.
It’s worth being honest about the evidence here. RxList, a pharmacology database, lists star anise’s effectiveness for cough and lung inflammation as having “insufficient evidence to rate.” That doesn’t mean it doesn’t work. It means no rigorous clinical trials have confirmed the effect in humans. The anti-inflammatory properties of its compounds are real and well-documented in lab research, which gives the traditional use some biological plausibility. But if you’re dealing with a persistent cough or respiratory infection, star anise tea is better thought of as a comfort measure than a treatment.
The Tamiflu Connection
You may have heard that star anise is “the plant Tamiflu comes from,” which is technically true but can be misleading. Shikimic acid extracted from star anise is the raw material that pharmaceutical manufacturers use to synthesize oseltamivir through a complex, multi-step chemical process. Drinking star anise tea does not give you a dose of Tamiflu. The shikimic acid in a cup of tea has not been chemically converted into oseltamivir, so it won’t act as an antiviral drug in your body.
This distinction matters because during flu outbreaks, star anise tea sometimes gets promoted as a natural flu treatment. While the spice is a fascinating piece of the Tamiflu supply chain, steeping the pods in hot water is not a substitute for antiviral medication.
Antioxidant and Anti-Inflammatory Properties
Star anise contains polyphenols and flavonoids that act as antioxidants, neutralizing free radicals that contribute to cell damage and chronic inflammation. Modern research has confirmed that compounds in the roots, leaves, and fruits of the plant exhibit analgesic (pain-relieving) and anti-inflammatory properties. For tea drinkers, this translates into a mild, general anti-inflammatory effect similar to what you’d get from other herbal teas like chamomile or ginger. It’s not powerful enough to replace an anti-inflammatory medication, but as a daily habit, it contributes to an overall anti-inflammatory dietary pattern.
A Serious Safety Concern: Chinese vs. Japanese Star Anise
This is the single most important safety fact about star anise tea. There are two species that look nearly identical: Chinese star anise (Illicium verum), which is the safe culinary spice, and Japanese star anise (Illicium anisatum), which is toxic. Japanese star anise contains a neurotoxin called anisatin that blocks a key receptor in the brain and nervous system. Ingesting it can cause seizures, vomiting, and serious neurological symptoms. Poisoning cases have been reported in both babies and adults, often from products contaminated with or mislabeled as the safe Chinese variety.
The two species are so visually similar that even trained eyes can struggle to tell them apart. To stay safe, buy star anise only from reputable spice retailers who specifically sell Illicium verum. Avoid purchasing loose, unpackaged star anise from sources you can’t verify.
Caution During Breastfeeding
Star anise tea has a reputation in some cultures as a remedy for colic in infants or as a galactagogue (a substance to boost milk supply). This is potentially dangerous. The E-lactation database, which evaluates the safety of substances during breastfeeding, rates star anise as “Very High Risk” and does not recommend its use while nursing. Anethole is neurotoxic at certain doses and can pass into breast milk. Additionally, star anise has estrogenic properties that may actually decrease milk production, the opposite of the intended effect. Nursing parents should avoid star anise tea entirely.
How to Brew Star Anise Tea
Place one to two whole star anise pods in a mug and pour about 8 ounces of boiling water over them. Let the tea steep for 10 to 15 minutes. The longer you steep, the stronger the flavor and the more compounds you’ll extract. You can add honey, a slice of ginger, or a cinnamon stick to complement the licorice notes. Some people crush the pods slightly before steeping to release more of the essential oils.
One to two cups a day is a reasonable amount. Because anethole can be irritating in large quantities, drinking excessive amounts of star anise tea may cause nausea or interact with certain medications, particularly hormone-sensitive ones given its mild estrogenic activity.