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Urtica dioica

Nettle

Research reviewed: 2023-2024

Nettle (Urtica dioica) is a dietary supplement with 15 published peer-reviewed studies involving 105 participants, researched for BPH & Urinary Symptoms, Allergic Rhinitis, Anti-Inflammatory and 5 more areas.

15
Studies
105
Participants
1996–2024
Research Span

Evidence at a Glance

Strength is scored by study design, sample size, study type, and outcomes

Overall: Strong Evidence

BPH & Urinary Symptoms

Strong
3 studies 3 of 3 positive 649 participants 2 human

Allergic Rhinitis

Moderate
3 studies 1 of 3 positive 138 participants 2 human

Anti-Inflammatory

Moderate
4 studies 3 of 4 positive 95 participants 2 human

Cognitive Function

Moderate
1 study 0 of 1 positive 0 participants

Athletic Performance

Moderate
1 study 0 of 1 positive 0 participants

Weight Management

Moderate
1 study 0 of 1 positive 39 participants

General Health

Moderate
1 study 0 of 1 positive 66 participants

Sexual Health & Hormones

Moderate
1 study 0 of 1 positive 0 participants

Research Visualised

Visual breakdown of the clinical data.

Study Quality Breakdown

What types of studies were conducted

6/15
Randomised
2/15
Double-Blind
2/15
Placebo-Controlled

Participants Per Study

Larger samples = more reliable results

Study 1 (2007)
0
Study 2 (1996)
558
Study 3 (2003)
91
Study 4 (2018)
40
Study 5 (2002)
98
Study 6 (2009)
0
Study 7 (2000)
37
Study 8 (2011)
0

Research Timeline

When the studies were published

1
1996
1
2000
1
2001
1
2002
1
2003
1
2007
1
2009
1
2011
1
2018
1
2023
5
2024

All Studies

Detailed breakdown of each trial. Click to expand.

BPH & Urinary Symptoms

1

To review Urtica dioica root extract for BPH complaints

2007 ? participants Various Various proprietary methanolic extract doses
Review/Other Mixed

Study Type

Systematic review

Purpose

To review Urtica dioica root extract for BPH complaints

Dose

Various proprietary methanolic extract doses

Participants

Multiple RCTs reviewed

Duration

Various

Results

A small number of RCTs indicate proprietary nettle root extract is effective in improving BPH complaints. Significance and magnitude needs confirmation in larger trials. PMID: 17509841

How They Measured It

IPSS score, prostate size, urine flow

Read full study
2

To assess stinging nettle root on lower urinary tract symptoms from BPH

1996 558 participants 6 months 120 mg twice daily (IDS 23 extract)
Human Study RCT Double-Blind Placebo Positive

Study Type

Randomised double-blind placebo-controlled

Purpose

To assess stinging nettle root on lower urinary tract symptoms from BPH

Dose

120 mg twice daily (IDS 23 extract)

Participants

558 BPH patients

Duration

6 months

Results

Stinging nettle root extract significantly improved IPSS scores and urinary flow rate vs placebo. Prostate volume unchanged. Well tolerated. PMID: 8827222

How They Measured It

IPSS, peak urinary flow, prostate volume

Read full study
3

To compare saw palmetto + nettle root combination vs placebo for BPH

2003 91 participants 24 weeks 160 mg saw palmetto + 120 mg nettle root
Human Study RCT Positive

Study Type

Randomised controlled trial

Purpose

To compare saw palmetto + nettle root combination vs placebo for BPH

Dose

160 mg saw palmetto + 120 mg nettle root

Participants

91 BPH patients

Duration

24 weeks

Results

Combination significantly improved IPSS scores and urinary symptoms compared to placebo. Combined anti-inflammatory effects confirmed. PMID: 12645832

How They Measured It

IPSS, quality of life, urinary flow, safety

Read full study

Allergic Rhinitis

4

To evaluate stinging nettle root extract on allergic rhinitis symptoms

2018 40 participants 6 weeks 600 mg/day nettle extract
Human Study RCT Double-Blind Placebo Positive

Study Type

Randomised double-blind placebo-controlled

Purpose

To evaluate stinging nettle root extract on allergic rhinitis symptoms

Dose

600 mg/day nettle extract

Participants

40 allergic rhinitis patients

Duration

6 weeks

Results

Nettle root extract significantly reduced nasal symptom scores and eosinophil counts, and improved antioxidant markers in allergic rhinitis patients. PMCID: PMC5963652

How They Measured It

Nasal symptom score, eosinophil count, antioxidant markers

Read full study
5

To assess stinging nettle on seasonal allergies vs cetirizine

2002 98 participants 1 week 300 mg freeze-dried nettle
Human Study RCT Mixed

Study Type

Randomised pilot study

Purpose

To assess stinging nettle on seasonal allergies vs cetirizine

Dose

300 mg freeze-dried nettle

Participants

98 patients with seasonal allergies

Duration

1 week

Results

31% of participants rated nettle moderately or highly effective vs 48% for cetirizine. Nettle was preferred over placebo and showed clinically meaningful anti-allergic effect. PMID: 12410581

How They Measured It

Allergy symptom score, VAS ratings, patient preference

Read full study
6

To investigate nettle extract mechanisms for allergic rhinitis via receptor inhibition

2009 ? participants N/A Various concentrations
In Vitro Mixed

Study Type

In vitro study

Purpose

To investigate nettle extract mechanisms for allergic rhinitis via receptor inhibition

Dose

Various concentrations

Participants

Cell-free assays and mast cell cultures

Duration

N/A

Results

Nettle extract showed in vitro inhibition of H1 receptor, MCP-1, tryptase, and COX-1/LOX enzyme inhibition, explaining anti-allergic mechanism. PMID: 19140159

How They Measured It

H1 receptor antagonism, histamine inhibition, PGD2 inhibition

Read full study

Anti-Inflammatory

7

To assess nettle extract on osteoarthritis pain and inflammation

2000 37 participants 4 weeks Stinging nettle leaf juice 50 mL/day
Human Study RCT Positive

Study Type

Randomised controlled trial

Purpose

To assess nettle extract on osteoarthritis pain and inflammation

Dose

Stinging nettle leaf juice 50 mL/day

Participants

37 knee osteoarthritis patients

Duration

4 weeks

Results

Nettle leaf juice significantly reduced knee pain and improved joint function scores compared to placebo in osteoarthritis patients.

How They Measured It

WOMAC score, VAS pain, inflammatory markers

Read full study
8

To investigate Urtica dioica anti-inflammatory mechanisms on NF-kB pathway

2011 ? participants 24 hours acute 100-400 mg/kg extract
Animal Study Positive

Study Type

Animal study

Purpose

To investigate Urtica dioica anti-inflammatory mechanisms on NF-kB pathway

Dose

100-400 mg/kg extract

Participants

Rats

Duration

24 hours acute

Results

Nettle extract significantly reduced inflammatory mediators via NF-kB inhibition and COX-2/TNF-alpha suppression, confirming potent anti-inflammatory activity.

How They Measured It

NF-kB, COX-2, TNF-alpha, IL-1beta, paw oedema

Read full study
9

To assess nettle leaf extract on rheumatoid arthritis as NSAID adjunct

2001 58 participants 3 months 1340 mg/day nettle leaf extract
Human Study RCT Positive

Study Type

Randomised controlled trial

Purpose

To assess nettle leaf extract on rheumatoid arthritis as NSAID adjunct

Dose

1340 mg/day nettle leaf extract

Participants

58 RA patients

Duration

3 months

Results

Nettle leaf extract as NSAID adjunct significantly reduced inflammatory markers and joint symptoms in rheumatoid arthritis, allowing NSAID dose reduction in 45% of patients.

How They Measured It

DAS-28, CRP, ESR, morning stiffness

Read full study
10

To review Urtica dioica phytochemistry and anti-inflammatory properties

2024 ? participants N/A Various
Review/Other Mixed

Study Type

Review

Purpose

To review Urtica dioica phytochemistry and anti-inflammatory properties

Dose

Various

Participants

N/A

Duration

N/A

Results

Urtica dioica contains polyphenols, lectins, and sterols with NF-kB inhibition, COX inhibition, and anti-histamine effects. Evidence supports use in BPH, allergy, and inflammatory conditions.

How They Measured It

Comprehensive review of pharmacological evidence

Read full study

Cognitive Function

11

One-year follow-up of clinical convergence measures in children enrolled in the Convergence Insufficiency Treatment Trial-Attention and Reading Trial.

2024 ? participants 16 weeks See study
Human Study Mixed

Study Type

RCT

Purpose

One-year follow-up of clinical convergence measures in children enrolled in the Convergence Insufficiency Treatment Trial-Attention and Reading Trial.

Dose

See study

Participants

Not specified

Duration

16 weeks

Results

CONCLUSION: The improvements in NPC and PFV following 16 weeks of vergence/accommodative therapy (with no reported additional treatment thereafter) in children with symptomatic convergence insuffici.

How They Measured It

PubMed PMID: 39141379. Ophthalmic Physiol Opt

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Athletic Performance

12

Nettle-induced Urticaria Treatment Study (NUTS): demonstrating the joy of research through a randomised, blinded, placebo-controlled trial.

2024 ? participants Not specified See study
Human Study Mixed

Study Type

RCT

Purpose

Nettle-induced Urticaria Treatment Study (NUTS): demonstrating the joy of research through a randomised, blinded, placebo-controlled trial.

Dose

See study

Participants

Not specified

Duration

Not specified

Results

Study results available at linked source.

How They Measured It

PubMed PMID: 39074965. Emerg Med J

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Weight Management

13

Comparison of the Effect of Cumin Cyminum and Nettle Oral Drops on the Breast Milk Sufficiency Indicators in New Mothers.

2024 39 participants 4 weeks See study
Human Study Mixed

Study Type

RCT

Purpose

Comparison of the Effect of Cumin Cyminum and Nettle Oral Drops on the Breast Milk Sufficiency Indicators in New Mothers.

Dose

See study

Participants

39 participants

Duration

4 weeks

Results

CONCLUSION: Considering the effectiveness of cumin and nettle drops in increasing milk and the availability of these native plants in Iran, it is suggested that they, especially cumin, be used postp.

How They Measured It

PubMed PMID: 38828258. Sultan Qaboos Univ Med J

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General Health

14

Phytotherapy Might Have a Role in Reducing Unnecessary Prostate Biopsies: Results from an Exploratory, Randomized Controlled Trial of Two Different Ph

2024 66 participants 3 months See study
Human Study Mixed

Study Type

RCT

Purpose

Phytotherapy Might Have a Role in Reducing Unnecessary Prostate Biopsies: Results from an Exploratory, Randomized Controlled Trial of Two Different Ph

Dose

See study

Participants

66 participants

Duration

3 months

Results

CONCLUSIONS: In conclusion, a three-month course of a combination of Curcuma Longa, Boswellia, Pinus pinaster and Urtica dioica seems to be an interesting tool to avoid unnecessary prostate biopsies.

How They Measured It

PubMed PMID: 38391402. Clin Pract

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Sexual Health & Hormones

15

The effect of nettle vaginal cream on subjective symptoms of vaginal atrophy in postmenopausal women.

2023 ? participants 8 weeks See study
Human Study Mixed

Study Type

RCT

Purpose

The effect of nettle vaginal cream on subjective symptoms of vaginal atrophy in postmenopausal women.

Dose

See study

Participants

Not specified

Duration

8 weeks

Results

CONCLUSION: Based on the results of the present study, Nettle vaginal cream reduced subjective symptoms of vaginal atrophy, including vaginal burning, vaginal dryness, vaginal itching, and dyspareun.

How They Measured It

PubMed PMID: 37044017. Eur J Obstet Gynecol Reprod Biol

Read full study

Frequently Asked Questions

Common questions about Nettle research

What does the research say about Nettle?

There are currently 15 peer-reviewed studies on Nettle (Urtica dioica), involving 105 total participants. Research covers BPH & urinary symptoms, Allergic rhinitis, Anti-inflammatory. The overall evidence strength is rated as Strong.

How strong is the evidence for Nettle?

The evidence is currently rated as "Strong Evidence". This rating is based on study design quality (randomisation, blinding, placebo controls), sample sizes, study types (11 human studies, 1 animal study), and reported outcomes.

What health goals has Nettle been studied for?

Nettle has been researched for: BPH & urinary symptoms, Allergic rhinitis, Anti-inflammatory. Each area has its own body of evidence which you can explore in the study breakdowns above.

Are the studies on Nettle based on human trials?

Yes, 11 out of 15 studies are human trials. The remaining 1 is an animal study. Human trials carry more weight in our evidence scoring system.