Artemisia annua and immunity: history, research and what we really know

Sweet wormwood (Artemisia annua L.) is often presented as a plant "for immunity". Where does this reputation come from? What does research show, and what does it not show? Here is the history of the plant, the real state of knowledge, how to take the 500 mg capsules and the precautions to know.

The short answer

Sweet wormwood is traditionally associated with the body's natural defences, and some of its compounds are studied in the laboratory. However, no robust study in humans shows that it strengthens immunity or that it protects against infections. A sweet wormwood capsule is a plant-based food supplement, not a treatment.

A plant with a history: from qinghao to the Nobel Prize

Native to the temperate regions of Asia, sweet wormwood belongs to the Asteraceae family. In China it is called qinghao. In the 4^th century, the physician Ge Hong already described a preparation of the plant soaked in cold water. It was by rereading this text that, in 1972, the team of researcher Tu Youyou isolated artemisinin, work that was awarded the Nobel Prize in Medicine in 2015. Purified and processed, this molecule became the basis of modern medicines prescribed by a doctor.

It is this history, more than any evidence, that earned the plant its reputation: a molecule that became a medicine does not make the whole plant a remedy.

What research is studying

• The plant's compounds: artemisinin and related lactones, flavonoids (casticin, chrysosplenetin…), essential oil and coumarins. Their content varies greatly from one harvest to the next.
• Laboratory tests: research teams observe the effect of certain extracts on cells in culture (in vitro) or in animals, including on immune system cells.
• Extracts, not capsules: this work most often concerns concentrated extracts or isolated molecules, at doses unrelated to a capsule of plant powder.

To learn more about these compounds, read Artemisia annua: plant compounds, research and precautions.

What research does not allow us to claim

A result obtained on cells or in mice says nothing about what happens in a person taking one capsule a day. To date, no robust study in humans shows that sweet wormwood capsules or herbal tea stimulate the body's defences, prevent winter infections or shorten an illness. If you often fall ill, talk to your doctor: a supplement replaces neither a diagnosis nor a treatment.

What really matters for your defences

Health authorities recall the same basics: enough sleep, a varied diet rich in fruit and vegetables, regular physical activity, and following your doctor's recommendations. If you choose to take sweet wormwood, it is in addition to these habits, never instead of them.

What does a 500 mg capsule contain?

• Composition: 500 mg of whole-plant powder of Artemisia annua L., 100% pure, with no excipients.
• Artemisinin neither isolated nor measured: the plant contains it naturally, in small and variable amounts. It is neither standardised nor guaranteed.
• Format: 100 capsules per box; the pack of 3 boxes contains 300.

How to take sweet wormwood capsules

• Dose: 1 capsule a day. Do not exceed 2 capsules a day, and only on the advice of a healthcare professional.
• When: in the morning, 15 to 30 minutes before a meal, with a large glass of water.
• Duration: courses of 20 to 30 days, which can be repeated after a short break.
• How long a box lasts: 100 days at 1 capsule a day; about 10 months with the pack of 3 boxes.

More details in our guide How many sweet wormwood capsules should you take?

Capsules, herbal tea or extract?

• Capsules: a fixed amount of plant, no taste, easy to carry.
• Herbal tea: the 60 sweet wormwood tea bags, for the ritual of a hot drink. See how to prepare the herbal tea and when to drink it.
• Liquid extract: the pure 500 ml liquid extract, to be diluted.

Precautions for use

• Not recommended for pregnant or breastfeeding women or for children.
• Avoid in case of allergy to plants of the Asteraceae family (daisy, chrysanthemum, wormwoods…).
• If you take any medication, follow a long-term treatment, have an autoimmune disease, or a liver or kidney problem, ask your doctor or pharmacist for advice before starting: the plant may interact with certain medicines.
• Do not exceed the stated dose. A food supplement is not a substitute for a varied and balanced diet or a healthy lifestyle.

Frequently asked questions

Does Artemisia annua strengthen the immune system?

This has not been demonstrated. Tradition associates the plant with the body's natural defences, and some compounds are studied in the laboratory, but no robust study in humans shows that sweet wormwood capsules strengthen immunity.

Can I take it to avoid a cold or flu?

No, this is not a demonstrated use. To protect yourself from seasonal infections, follow the advice of your doctor or pharmacist.

Is the artemisinin in the capsules the same as in medicines?

It is the same molecule, but in completely different conditions. Medicines contain purified, dosed derivatives prescribed by a doctor. A capsule contains whole-plant powder, in which artemisinin is present in small, unmeasured amounts.

What are the possible side effects?

Digestive problems (nausea, discomfort) and allergic reactions are possible, especially in people sensitive to Asteraceae. In case of a reaction, stop taking it and ask a healthcare professional for advice. To know what to expect from a course, read Artemisia annua capsules: how long before you see a result?

See all our products in the Artemisia collection. Read also: Sweet wormwood: uses, research and precautions and Artemisia annua and digestion: uses, intake and precautions.

Food supplement. This article is provided for information purposes and does not replace the advice of a healthcare professional.