Stinging Nettle Root: Questions Answered

Short, sourced answers to common questions about stinging nettle root (Urtica dioica). Each answer comes from one of our research articles, which list the studies, the doses used and what the evidence does not show. This is general information, not medical advice.

The basics

What is stinging nettle root?

What is stinging nettle root?
It is the underground part of the stinging nettle plant, Urtica dioica. It is used as a traditional herbal remedy for the urinary symptoms of BPH and sold as capsules, extracts, tinctures and teas.

Is stinging nettle root the same as nettle leaf?
No. They are different parts of the plant with different compounds, traditional uses and research. The EMA lists root for urinary symptoms of BPH and leaf for minor joint pain and urinary flushing.

Read the full article: What is stinging nettle root?

Nettle root vs nettle leaf

Is nettle root the same as nettle leaf?
No. They come from the same species, Urtica dioica, but the root is the underground part and the leaf is above ground. The EMA lists different traditional uses for each: urinary symptoms of BPH for root, and minor joint pain and urinary flushing for leaf.

Which part of the nettle is used for prostate health?
Trials on BPH used root extracts, or a combination of root and saw palmetto extracts. Leaf has not been the focus of the prostate research we cite.

Read the full article: Nettle root vs nettle leaf

Traditional use and history

Is stinging nettle root an ancient remedy?
Nettle has a long history as a food and folk remedy. The EMA report says root was first mentioned as a herbal medicine in the 16th century by Paracelsus and Matthiolus and that folk medicine relied more on the herb and leaves. Use of the root for urinary tract disorders dates from the 1950s.

What is nettle root traditionally used for?
The EMA lists folk uses including dropsy, diarrhoea, worms, blood purifying, diuresis, gout and rheumatic disorders, dandruff and hair preparations, and urinary complaints. Its accepted traditional indication today is relief of urinary symptoms related to BPH after a doctor has excluded serious conditions.

Read the full article: Traditional use and history

Prostate and urinary research

Stinging nettle root for BPH

Does stinging nettle root shrink the prostate?
Results vary. One 620-man trial measured a fall from 40.1 to 36.3 cc, but the other trials in our article did not report a clear size change, and reviewers say the size of any effect is still to be confirmed.

How long does stinging nettle root take to work for BPH?
The controlled trials in our article measured results after 12 weeks to 12 months, so any benefit is judged over months, not days. Review your symptoms with your doctor rather than relying on a short trial period.

Read the full article: Stinging nettle root for BPH

Urinary flow and night-time urination

Does nettle root improve urine flow?
Results vary. In a 620-man trial, peak flow rose by 8.2 mL/s with nettle and 3.4 mL/s with placebo. In a 246-man, 12-month trial the rise was about the same as placebo, and the authors said a strong increase in flow should not be expected.

Does nettle root help with night-time urination?
A combined analysis of four trials of a nettle root and saw palmetto product found 0.8 fewer night-time voids against 0.6 with placebo. Nettle root alone has not been tested for nocturia as a main outcome in the trials cited in our article.

Read the full article: Urinary flow and night-time urination

Does it block DHT?

Does stinging nettle root block DHT?
It has not been confirmed. The EMA describes the mechanism of action as unclear, a review judged 5-alpha-reductase less likely to be involved, and none of the nettle root trials cited in our article reports blood DHT.

Is nettle root a natural 5-alpha-reductase inhibitor?
Some laboratory and animal studies reported 5-alpha-reductase activity for certain extracts, but these findings have not been confirmed in men, and the plant part and solvent differed between studies.

Read the full article: Does it block DHT?

Testosterone and SHBG

Does stinging nettle root raise testosterone?
Not in the studies cited in our article. Testosterone was unchanged in the 620-man trial, and the EMA reports no significant change in sex hormone parameters in two of the three studies it describes. These studies enrolled men with BPH symptoms.

Does nettle root increase free testosterone?
This has not been shown in men. A cell-culture study found that a nettle root lignan can displace testosterone from SHBG, which is a possible mechanism, but SHBG fell in men without a reported testosterone change.

Read the full article: Testosterone and SHBG

Nettle root vs saw palmetto

Which is better for BPH, nettle root or saw palmetto?
No trial we found compares the two herbs alone, so there is no direct answer. Saw palmetto alone was no better than placebo in a Cochrane review and in two large, long trials. Nettle root alone has fewer, smaller trials, two of which found lower symptom scores than placebo, but results on urine flow vary and the largest trial has not yet been repeated. Ask your doctor about options with stronger evidence.

Does saw palmetto work for BPH?
Early reviews and an 85-man trial suggested it did, but the larger and longer placebo-controlled trials did not. A Cochrane review of 32 trials in 5,666 men found that saw palmetto, even at double and triple doses, did not improve urine flow or prostate size, and in two high-quality long trials it was not better than placebo for symptoms.

Read the full article: Nettle root vs saw palmetto

Using it safely

Dosage, timing and forms

How much stinging nettle root should I take?
No single dose is established. Trials of nettle root extract report 450 mg a day and a 459 mg dry extract, and the EMA monograph lists regimens that depend on the extract type, for example 460 mg once daily of a methanolic dry extract. For a supplement, follow the label (our label suggests 1 to 2 capsules daily, preferably with meals) or the advice of your healthcare provider.

Does a 750 mg capsule mean 750 mg of nettle root?
No. In our product, 750 mg is the weight of the extract. With a 10:1 ratio it is made from about 7,500 mg of dried root. Neither number can be compared directly with trial doses, because the trials used different extracts.

Read the full article: Dosage, timing and forms

Side effects and who should avoid it

Is stinging nettle root safe?
In the clinical trials cited in our article, adverse events were few and not more frequent than with placebo, and, on the basis of its traditional use, the EMA concluded that nettle root proved not to be harmful under the specified conditions of use. Some groups should check with a doctor first: people allergic to nettle, people who are pregnant or breastfeeding, anyone under 18, and anyone with urinary symptoms that have not been checked.

What are the side effects of nettle root?
The EMA lists stomach and bowel complaints (nausea, heartburn, diarrhoea, constipation, fullness, gas) and allergic skin reactions (itching, rash, hives). Their frequency is listed as not known.

Read the full article: Side effects and who should avoid it

Medicine interactions

Does stinging nettle root interact with medicines?
No interactions have been reported to the EMA, but the agency also notes that specific interaction data are not available, and no clinical study has tested nettle root taken together with another medicine. Ask your doctor or pharmacist before starting.

Can I take nettle root with blood pressure medicines?
No study found has tested the combination. Tell your prescriber before you start, keep any blood pressure checks they have asked for, and report dizziness.

Read the full article: Medicine interactions

How to choose a supplement

How do I know a nettle root supplement is real?
No label alone proves that. Check that it names the root, the species, the extract ratio and the amount, look for a verifiable third-party seal, and ask the seller for a batch certificate of analysis. Studies of other herbs found label mismatches in some products, so independent testing of a batch is the most direct check.

What does 10:1 mean on a nettle root label?
It means roughly 10 parts of dried plant were used to make 1 part of extract. A 750 mg capsule of 10:1 extract corresponds to about 7,500 mg of dried root.

Read the full article: How to choose a supplement

Other topics people ask about

Blood sugar

Does nettle root lower blood sugar?
We found no trial of nettle root alone that measured blood sugar. The trials that report lower fasting glucose used leaf extract or mixed herbal products.

How much did nettle lower blood sugar in the trials?
Two pooled analyses report a fall in fasting blood glucose of about 17 to 18 mg/dL on average, with wide differences between trials. They differ on HbA1c.

Read the full article: Blood sugar

Blood pressure and heart health

Does nettle root lower blood pressure?
We found no human trial of nettle root that measured blood pressure. The root has been tested in one laboratory and animal study, which reported a transient fall in blood pressure in anaesthetised rats.

Does nettle leaf lower blood pressure?
Leaf extract lowered blood pressure in a rat model of hypertension. In people with type 2 diabetes, two single trials found no change, while a pooled analysis of 13 trials reported systolic pressure about 5 mmHg lower.

Read the full article: Blood pressure and heart health

Kidney and urinary tract health

Is nettle root good for the kidneys?
We found no human trial of nettle root on kidney function. The kidney studies we found used leaf or aerial-part extracts in rats.

Does nettle root help with kidney stones?
No human trial of nettle root on kidney stones was found. A rat study of an aerial-part extract reported less calcium oxalate deposited in the kidney, and the EMA records folk use against kidney stones as history only.

Read the full article: Kidney and urinary tract health

Joint pain and inflammation

Is stinging nettle root good for joint pain?
We found no human trial of nettle root alone for joint pain. The human trials on nettle and joints used leaf applied to the skin or multi-ingredient products, so they do not tell us about root capsules.

Does nettle root reduce inflammation?
Some nettle extracts, including root extracts, reduced inflammation markers in cell experiments. Cell results do not establish that a capsule reduces inflammation in people.

Read the full article: Joint pain and inflammation

Hair loss

Does stinging nettle root help hair growth?
We found no human study of nettle root or any nettle product on hair growth or hair loss. The research so far is a cell experiment on leaf extract and computer modelling.

Is nettle root a natural DHT blocker for hair?
That description comes from prostate-related lab and animal work. DHT lowering by nettle root has not been confirmed in men, and hair follicles have not been studied.

Read the full article: Hair loss

These statements have not been evaluated by the Food and Drug Administration. Real Herbs products are not intended to diagnose, treat, cure, or prevent any disease. Talk to your doctor or pharmacist before using any supplement.