Educational information, not medical advice — ask your doctor or midwife.
Tarragon is a leafy green herb used in French cooking. The plant is Artemisia dracunculus. Across Europe it is often called estragon.
There are two main types. French tarragon has the sweet, anise-like taste cooks want. Russian tarragon is coarser and milder, and it is the type used in most supplement research.
In folk use it was given for poor appetite, wind, toothache and poor sleep. Today it is sold as a dried herb, a tea, an oil and a capsule. Supplement labels often point to blood sugar and digestion.
Here is the honest verdict. Human evidence is thin. A few small trials of a Russian tarragon extract hint at modest blood sugar effects, and nothing is settled.
Long use in food and folk medicine is not proof that tarragon works. It is also not proof that it is safe in large or concentrated doses.
No one has shown how tarragon works in the body in people. Most of what is claimed comes from lab dishes and animals.
In animal and cell studies, a Russian tarragon extract called PMI-5011 appears to help insulin work better. Insulin is the hormone that moves sugar out of the blood. Whether this happens in people in any useful way is unproven.
In test tubes, tarragon oil slows the growth of some bacteria and fungi. That is not the same as treating an infection in a person.
Lab work also points to anti-inflammatory action from the plant's flavonoids. Flavonoids are common plant colour and defence chemicals. This has not been confirmed in human trials.
The numbing feel in the mouth from fresh leaves or the oil is real and easy to notice. Folk use for toothache likely grew from it. It is a surface effect, not a treatment for the cause of tooth pain.
Most people meet tarragon as food. The common forms are:
Fresh leaves, used in sauces, chicken, eggs and fish. Dried leaves, sold in jars as a kitchen herb. Tarragon vinegar, made by steeping the herb.
A tea or infusion made from dried leaves. Capsules or tablets of dried leaf. Liquid extracts and tinctures, often from Russian tarragon.
Essential oil is also sold. It is very concentrated. It is meant for scent and dilute skin use, not for swallowing.
Tarragon has a long, well recorded place in European kitchens and herbals. The Latin name dracunculus means little dragon. Writers linked this to the coiled roots, and to old beliefs about snake and dragon bites.
The herb reached Europe through Arab medicine in the Middle Ages. Herbalists of the time listed it for poor appetite and sluggish digestion.
Later European folk use added more claims. Chewed leaves were used to dull toothache. Teas were taken for wind, water retention and restless sleep.
French cooking then made it a staple herb. It is one of the fines herbes, and the base of béarnaise sauce. That culinary role, not medicine, is why most people know it.
Stop tarragon and get urgent medical help if your lips, tongue or face swell, or if breathing gets tight. That is an allergic reaction.
See a doctor promptly if you notice yellow skin or eyes, dark urine, or pain under your right ribs. These can be liver warning signs.
See a doctor if you bruise or bleed more easily than usual.
If you have diabetes, check in with your doctor if your sugar readings drop lower than normal. Signs include shaking, sweating, hunger and confusion.
Toothache that lasts more than a day or two needs a dentist, not a herb.
In the United States, tarragon is an ordinary food herb and flavouring, and is on the FDA's GRAS list. Capsules and extracts are sold as supplements, which are not checked for effect before sale.
In the European Union and the United Kingdom it is sold freely as food. European rules limit how much added estragole may be put into food and drink.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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