Anise Oil Benefits: What the Research Does and Does Not Show
Most claims about anise oil benefits outrun the published trials. The human studies that exist are few, small and mostly from one country, and they tested aniseed powder, tea, extracts or oral capsules, not aromatherapy. No study here shows that a bottle of essential oil does anything for a health condition.
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Shop Now →We sell a single aromatic and cosmetic ingredient, so we hold ourselves to a stricter standard than most pages that rank for "anise oil benefits." This guide reports what researchers examined, in what form, in whom, and what they could not tell us. It does not recommend anise oil for any health purpose, and nothing here replaces advice from a pharmacist or physician.
The evidence at a glance
This table is the whole article in one view. Each row is a topic people search for, followed by the preparation researchers actually tested and our rating of how much the evidence can support.
| Topic | What was actually tested | Evidence strength | Main limit |
|---|---|---|---|
| Digestion and bloating | Aniseed powder by mouth; enteric-coated anise oil capsules; a four-herb compound | Limited | Small trials, similar research groups, oral forms |
| Cough and congestion | Aniseed tea (traditional use in an EMA monograph); no anise-only cough trial found | Limited (traditional use only) | Based on long-standing use, not trial data |
| Menstrual cramps | A multi-herb capsule that included anise extract | Limited | Anise cannot be separated from the other herbs |
| Head lice | A coconut and anise spray on the scalp, compared with a pesticide lotion | Limited | Combination product, topical use, one randomized trial |
| Sleep and relaxation | No trial of anise on sleep found; anethole studied in mice | Lab-only or animal-only | Nothing in people to report |
| Germ-killing in a dish | Anise oil against cultured bacteria and yeast | Lab-only | A dish is not a human body |
Notice what is missing: no row reads "strong." We found no topic where several well-sized, independent, blinded trials agree. That is the central finding of this review.
How we rated the evidence
The four ratings are our own plain-language shorthand, not an official scale.
- Strong: several adequately sized randomized trials or a systematic review that agree, ideally from independent research groups.
- Moderate: at least one well-run randomized trial plus some supporting data, but limited replication.
- Limited: a handful of small or single-center trials, mixed preparations, or results that cannot be separated from other ingredients.
- Lab-only or animal-only: cell cultures, test tubes or animal experiments. These are useful for generating questions and say very little about what happens in a person.
We looked each study up on PubMed, PubMed Central or the publisher record before describing it, and where we could not confirm a detail we left it out. One caution applies to everything below: a trial that found a difference is a single data point, not a verdict, and a systematic review published in 2026 found too little anise oil data to pool into a meta-analysis for irritable bowel syndrome (Meyer and colleagues, Phytotherapy Research, 2026).
The most important distinction: what was swallowed versus what is smelled
Nearly every positive human result for anise involved a preparation taken by mouth: grams of aniseed powder, a tea made from the fruit, or capsules designed to release anise oil in the intestine. Those are medicinal dosage forms studied under medical supervision. They are not the same as opening a bottle of essential oil in a room or blending it into a cosmetic product. Dose, route and chemistry all differ.
It follows that a trial of aniseed powder cannot be borrowed as evidence for a diffuser. Our oil is sold for aromatic and cosmetic use, and we do not suggest swallowing it. If you have wondered about eating essential oil, see our page on grades, labels and limits for edible anise oil.
Digestion: the most studied area, still limited
Digestive complaints are where anise has the most human trials. One double-blind randomized trial in Isfahan, Iran, enrolled 107 adults with postprandial distress syndrome, a form of functional dyspepsia, and gave 47 of them 3 g of aniseed powder after each meal for four weeks against a corn-starch placebo (Ghoshegir and colleagues, Journal of Research in Medical Sciences, 2015). Symptom scores were lower in the anise group at weeks 2, 4 and 12. A three-arm trial of 120 people with irritable bowel syndrome tested enteric-coated anise oil capsules against placebo and a branded comparator (Mosaffa-Jahromi and colleagues, Journal of Ethnopharmacology, 2016).
Those are real results, and we rate the area limited because the trials were small, came from a small number of Iranian groups, used different preparations, and lack the independent replication that would make them strong. The full story, including a reporting oddity in the first trial's abstract, is in our evidence review on anise and digestion.
Coughs and congestion: traditional use is not a trial
The European Medicines Agency's herbal committee (HMPC) has a monograph on aniseed fruit that lists, as a traditional use, an expectorant in cough associated with cold. The monograph states that the product is for use in specified indications "exclusively based upon long-standing use," meaning it is a record of tradition and not a verdict from trials. It also does not recommend use in children under 12 and caps use at two weeks (EMA/HMPC/321184/2012). We did not find a randomized trial of anise alone for cough. Our position: a cough that lasts needs a clinician, not a bottle. Details, including steam burn risks, are in anise oil for coughs and congestion.
Menstrual cramps
A 2018 randomized trial in western Iran gave female students a capsule containing extracts of celery, anise and saffron against placebo (Shobeiri and colleagues, Obstetrics and Gynecology Science). Pain scores fell in the herbal group. But with three plants in one capsule, the result cannot be assigned to anise, and the authors themselves flag the small sample as a main limitation. See what the studies show on menstrual cramps.
Head lice
This is the one place where a trial tested anise on the skin. A randomized trial of 100 people with active head louse infestation compared a coconut and anise spray with 0.43% permethrin lotion, and reported success in 41 of 50 versus 21 of 50 (Burgess and colleagues, European Journal of Pediatrics, 2010). It was a formulated product with other ingredients, applied as a pest treatment, so it says nothing about a cosmetic or aromatic oil. A 2025 meta-analysis of plant-based head lice products concluded that results should be interpreted cautiously because of heterogeneity and small, unblinded studies (Chen and colleagues, PLOS Global Public Health). Our write-up is anise oil and head lice.
Sleep and relaxation
We found no randomized trial of anise or anise aroma on sleep. The anxiolytic-like findings for anethole, the main aroma compound, come from mice, and an inhalation study in mice used star anise fruit oil, a different plant. The National Center for Complementary and Integrative Health says of aromatherapy and insomnia that "little rigorous research has been done" (NCCIH). Read the sleep evidence explained.
Lab-only findings are not evidence for human use
Search for anise oil online and you will meet a lot of laboratory data. One 2023 study in the journal Plants exposed cultured bacterial and yeast strains to dilutions of anise oil and measured growth (Dumitrescu and colleagues). Findings like that tell chemists the oil is biologically active against microbes in a dish. They do not tell anyone that putting the oil on skin or in air does anything useful, and concentrations that affect cells in a dish may be irritating or harmful to people. Animal work has the same limit: a mouse given anethole by injection is not a person smelling a diffuser.
What the regulators actually say
EMA's HMPC adopted final monographs for aniseed fruit and for anise oil on 12 November 2013. For the fruit, the traditional-use indications are mild, spasmodic gastrointestinal complaints including bloating and flatulence, and as an expectorant in cough associated with cold, taken as a tea by adolescents over 12, adults and the elderly for no more than two weeks. For the oil, the monograph covers oral products, sets 50 to 200 microliters three times daily for adults, and contraindicates use in children and adolescents under 18 because of lack of data and the presence of estragole (EMA/HMPC/321185/2012). Both advise against use in pregnancy and lactation for lack of safety data, list allergy to anise, other Apiaceae plants or anethole as a contraindication, and say a doctor or qualified practitioner should be consulted if symptoms persist.
These are European herbal-medicine documents. They describe oral herbal medicinal products and do not apply to cosmetic or aromatic oils sold in the United States.
Using aromatic products safely
If you enjoy the scent of anise in a diffuser, candle or perfume, the safety basics matter more than any claimed benefit. Dilute before any skin contact, patch test, keep the bottle away from children and pets (our children's storage and use guide has the details), and ventilate. Our anise oil safety basics covers dilution and pets, pregnancy and breastfeeding explains why professionals advise caution, and hormones and medications lists who should ask a pharmacist first. People who are pregnant, take prescription drugs or have a chronic condition should speak to a physician or pharmacist before using any product with anethole. If you simply want the ingredient for scenting and craft work, our shop lists the sizes we carry, along with a published certificate of analysis.
Our position
Anise is a well-loved plant with a long cultural record, and a few small trials are interesting enough that larger, independent ones would be welcome. But the honest summary is that the research does not show that anise essential oil improves any health condition. It shows that certain oral aniseed preparations were studied for certain complaints, with limited results, and it shows laboratory activity that has not been translated into people. Anyone who writes "anise oil benefits" with a bulleted list of cures is working from a different evidence base than the one published. For the historical record behind the claims, read the history of anise in medicine and culture.
If you have a health concern, a persistent symptom, or questions about a trial mentioned here, speak with a physician or pharmacist. In the United States, Poison Control can be reached at 1-800-222-1222 if someone swallows essential oil.
Anise Essential Oil
Anise Essential Oil from our own shop, in sizes from 0.5 oz to bulk.
From $7.99
Shop Now →Sources & Further Reading
- EMA/HMPC, Community herbal monograph on Pimpinella anisum L., fructus (EMA/HMPC/321184/2012), 12 November 2013
- EMA/HMPC, Community herbal monograph on Pimpinella anisum L., aetheroleum (EMA/HMPC/321185/2012), 12 November 2013
- Ghoshegir SA et al. Pimpinella anisum in the treatment of functional dyspepsia: a double-blind, randomized clinical trial. J Res Med Sci. 2015
- Mosaffa-Jahromi M et al. Efficacy and safety of enteric coated capsules of anise oil to treat irritable bowel syndrome. J Ethnopharmacol. 2016
- Meyer A et al. Systematic review and meta-analysis: plant-based therapy for irritable bowel syndrome. Phytother Res. 2026
- Shobeiri F et al. Effect of Menstrugole on primary dysmenorrhea: a randomized clinical trial. Obstet Gynecol Sci. 2018
- Burgess IF et al. Clinical trial showing superiority of a coconut and anise spray over permethrin 0.43% lotion for head louse infestation. Eur J Pediatr. 2010
- Chen J et al. Therapeutic potential of plant-based therapies in pediculosis capitis: systematic review and meta-analysis. PLOS Glob Public Health. 2025
- Dumitrescu E et al. Pimpinella anisum L. essential oil, a valuable antibacterial and antifungal alternative. Plants. 2023
- National Center for Complementary and Integrative Health, Aromatherapy