Know2eat

Nettle

Urtica dioica

Herbs & Botanicals

What nettle may help with

Ranked by how strong the human evidence is — best supported first.

Best supportedProstate healthLimited evidence· 3 sources

Then, in order

About Nettle

Leaf or root preparations from stinging nettle. The two plant parts are used for entirely different purposes — leaf for allergy and joint symptoms, root for lower urinary tract symptoms — and are chemically distinct.

The leaf-versus-root distinction is the thing most nettle marketing ignores. Nettle root has a small European literature in benign prostatic hyperplasia, often as part of a combination with saw palmetto or pygeum; nettle leaf has thin evidence for allergic rhinitis and joint pain. Neither is well established, and combination trials cannot tell you what nettle did on its own.

Sold as
Leaf capsule, Root extract, Tea, Tincture, Freeze-dried leaf, Combination prostate formulas
Standardised to
Root products sometimes standardised to beta-sitosterol or lectin content — a product without this marker may not resemble what was studied.
Also known as
Stinging nettle, Urtica, Nettle leaf, Nettle root

What the research used

The amounts, forms and durations published trials of Nettle actually administered.

These are the amounts published trials administered — not a recommendation, and not a dose to copy. Trial participants were screened, supervised and given a characterised preparation. What is in a retail bottle is frequently not what was studied, and the amount that suits one person is not general advice.

  • Studied for Lower urinary tract symptoms with benign prostatic hyperplasia

    300–600 mg

    Limited

    Root extract, divided doses · 8–24 weeks

    Much of this evidence comes from fixed combinations with saw palmetto or pygeum, so the contribution of nettle alone cannot be separated out.

  • Studied for Allergic rhinitis

    600 mg

    Not enough

    Freeze-dried leaf, divided doses · 1 week

    From one small older trial with a self-reported endpoint; that is not enough to establish a dose.

This is general information about food, not medical advice. It cannot diagnose, treat or replace guidance from a clinician who knows your history.

When it was taken

Each window says whether a trial compared it against an alternative, or whether it is convention and pharmacology. Most timing advice is the second kind.

None of the timings below were directly compared in a trial. They reflect how the research happened to dose, or what the pharmacology implies — which is not the same as a timing being better.

  • With food

    Not enough

    Taken with meals for tolerability in most protocols. Not a tested variable.

    Timing was not directly compared. This reflects convention or how the compound behaves in the body, not a trial showing this window works better.

The evidence in depth

Best supported: Limited

What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how promising the supplement sounds. How we rate evidence.

Prostate health

Men's Health
Limited evidence

Some trials report improved urinary symptom scores in benign prostatic hyperplasia with nettle root, alone or in combination. Trials are small and mostly European, and symptom scores in this condition respond strongly to placebo.

Limited evidence. Early human work, or mostly lab and animal research.

View the 3 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Joint comfort

Joint Health
Not enough evidence

Evidence is limited for nettle leaf and joint pain. The few trials are small, some used topical application of the stinging plant itself, and none provide a dependable basis for a conclusion.

Not enough evidence. Not enough human research to say anything useful yet.

View the 4 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Respiratory function

Respiratory Health
Not enough evidence

There is not enough human research to say nettle leaf affects hay fever symptoms. One small trial is the basis for a large amount of marketing.

Not enough evidence. Not enough human research to say anything useful yet.

View the 1 source

Deep research mode adds each paper’s own conclusion and stated limitations.

Things to know

Interactions, contraindications and dose limits, most serious first. Concentrated extracts interact with medication in ways the whole plant does not, so this section carries more weight here than it does on a food page.

  • Worth knowing

    Prostate symptoms need assessment first

    Urinary symptoms in older men can indicate prostate cancer, infection or urinary retention. Managing them with a supplement before a proper assessment risks delaying a diagnosis.

  • Interaction

    Diuretics, blood pressure and glucose medication

    Interacts withDiuretics, antihypertensives, insulin, sulfonylureas

    Nettle has a traditional diuretic use and has been reported to lower blood pressure and blood glucose, so it may add to medication doing the same.

  • Interaction

    Vitamin K content and warfarin

    Interacts withWarfarin

    Nettle leaf is high in vitamin K, which can oppose warfarin and destabilise INR control.

  • Avoid

    Pregnancy

    Nettle has traditional uterine-stimulant use and is generally avoided in pregnancy in supplemental amounts, though it appears in some teas.

  • Allergy

    Skin reactions

    Handling fresh nettle causes the familiar sting, and allergic rashes to nettle preparations have been reported.

Evidence ratings on this page: 1 limited evidence, 2 not enough evidence.

Supplements are sold in the US without pre-market review of efficacy or safety. Nothing on this page is a recommendation to take Nettle, or a dose to follow.