Green Oat Extract (Oat Herb)

Also called Avena sativa herb, wild green oat extract, oat herb, oat straw, Avenae herba, green oat herb extract.

Best grade C across 5 graded outcomes Botanical Last checked Oct 21, 2026

The short answer

From 9 sources

Green oat extract comes from the leaves and stems of young oat plants and is sold for focus and stress. Single doses improved some attention and memory tasks in small trials, and a 4-week trial found working-memory gains, but a 12-week trial in older adults found none. Five of the cited trials were funded or co-authored by extract makers.

Every graded outcome on this page

5 rows · line = participants

Grade CCognitive accuracy and speed (systematic review of RCTs)Cognitionn 287
Grade CQuality of life, stress and sleep during smoking reductionStress and wellbeingn 145
Grade CWorking memory, multitasking and stress response over 4 weeksWorking memoryn 132
Grade CCognition after 12 weeks in older adultsCognitionn 37
Grade DAttention task speed and brain responses after a single doseAttentionn 20
2 more graded outcomes, in the evidence chapter

Key facts

Systematic review: A 2023 review of 6 trials (287 healthy adults) found single doses appeared to improve accuracy and speed; short-term daily use helped, longer-term use did not, and evidence quality was average¹
4-week trial: In 132 adults aged 35-65, 430 mg and 1,290 mg/day for 4 weeks improved a working-memory task and a multitasking task versus placebo; the middle 860 mg dose did not, and mood was unaffected³
12-week null result: In 37 healthy adults averaging 67 years, 1,500 mg/day for 12 weeks did not change any cognitive measure²
Single-dose trials: Single doses of 800 mg in middle-aged adults and 1,600 mg in older adults improved some timed and Stroop tasks (a higher 2,400 mg dose did not); the 800 mg trial authors suggest the best acute dose is at or below 800 mg^6,7
Industry: The extract makers (Frutarom/IFF for Neuravena, Anklam Extrakt for cognitaven) employed authors of or sponsored five of the cited trials^3,4,5,6,9

What it is

Green oat extract is made from the green aerial parts of the oat plant (Avena sativa) harvested before flowering, not from the oat grain.

How it works

Proposed

Green oat herb contains flavonoids and triterpene saponins. Animal work suggested effects on stress responses and memory, and a 2021 EEG study reported changes in brain responses linked to attention and error monitoring after a single dose. How these compounds act in people is not established.^4,6

Forms, side by side

3 forms named in our sources. The rest show what our data holds, and say plainly where it holds nothing yet.

Green Oat Extract (Oat Herb) forms compared

3 forms

Green Oat Extract (Oat Herb) forms compared: 3 forms by 3 attributes. Empty cells are labelled No data yet, or Not graded in the evidence row.
3 forms	Wild green oat herb extract (Neuravena)	Green oat herb extract (cognitaven)	Oat herb tea, tincture or juice (traditional preparations)
Absorption in people	No head-to-head human data²	No head-to-head human data³	No head-to-head human data⁸
GI tolerance	Well tolerated at 900 mg/day for 8 weeks.⁵	Side effects were minor and no more frequent than on placebo over 29 days.³	The EU herbal monograph lists hypersensitivity as the only contraindication and reports no known interactions.⁸
Studied for	Acute attention and memory, stress and wellbeing	Working memory and stress response	Traditional use for mild mental stress and sleep (EU, based on long-standing use)

Wild green oat herb extract (Neuravena)
Absorption in people
No head-to-head human data²
GI tolerance
Well tolerated at 900 mg/day for 8 weeks.⁵
Studied for
Acute attention and memory, stress and wellbeing
Green oat herb extract (cognitaven)
Absorption in people
No head-to-head human data³
GI tolerance
Side effects were minor and no more frequent than on placebo over 29 days.³
Studied for
Working memory and stress response
Oat herb tea, tincture or juice (traditional preparations)
Absorption in people
No head-to-head human data⁸
GI tolerance
The EU herbal monograph lists hypersensitivity as the only contraindication and reports no known interactions.⁸
Studied for
Traditional use for mild mental stress and sleep (EU, based on long-standing use)

What the human research says

Human trials only, one row per outcome. The form line shows what each trial actually tested. Grades follow our evidence-grading policy.

Trial map

5 graded outcomes, largest study first

5 graded outcomes: 3 improved, 1 mixed, 1 no effect. The largest, a 2023 systematic review of 287 people on cognitive accuracy and speed (systematic review of RCTs), found mixed results.

By sizeTable

1Cognitive accuracy and speed (systematic review of RCTs)

Mixed · Grade C · Systematic review, 287 people, 2023

Healthy adults in 6 randomized trials (3 crossover)

Dose, result and source

Every graded outcome on this page, largest study first
Outcome	Found	People	Study	Who was studied
Cognitive accuracy and speed (systematic review of RCTs)	Mixed	287	Grade C · Systematic review, 2023	Healthy adults in 6 randomized trials (3 crossover)
Quality of life, stress and sleep during smoking reduction	Improved	145	Grade C · RCT, 2024	Spanish adult smokers trying to cut down or quit
Working memory, multitasking and stress response over 4 weeks	Improved	132	Grade C · RCT, 2020	Healthy UK adults aged 35-65
Cognition after 12 weeks in older adults	No effect	37	Grade C · Crossover RCT, 2012	Healthy Australian adults averaging 67 years with normal cognition
Attention task speed and brain responses after a single dose	Improved	20	Grade D · RCT, 2021	Healthy Spanish adults

Every graded row

5 rows

Form tested

Showing 5 of 5 outcomes. Human trials only.

Grade CCognitive accuracy and speed (systematic review of RCTs)CognitionAcute benefit; long-term nullSystematic review
n 287 · 2023

Mixed Single doses appeared to improve accuracy and speed of performance. Short-term daily use improved cognitive function; longer-term daily use did not. Evidence was rated of average quality.

Design: Systematic review, n = 287, 2023
Population: Healthy adults in 6 randomized trials (3 crossover)
Form: Avena sativa extracts (various)
Dose: Varied between trials
Duration: Single dose to 12 weeks
Source: Reference 1 · PubMed 36657906 (opens PubMed)

Grade CQuality of life, stress and sleep during smoking reductionStress and wellbeingLower perceived stress; 66.7% vs 49.3% reducersRCT
n 145 · 2024

Improved Quality-of-life scores and perceived stress improved more than on placebo, and sleep quality improved while it worsened on placebo. More participants cut daily cigarettes by over 20% (66.7% vs 49.3%, p = 0.034). The product was well tolerated.

Design: RCT, n = 145, 2024
Population: Spanish adult smokers trying to cut down or quit
Form: Wild green oat extract (Neuravena)
Dose: 900 mg/day
Duration: 8 weeks (plus 4-week follow-up)
Source: Reference 5 · PubMed 38962436 (opens PubMed)

Grade CWorking memory, multitasking and stress response over 4 weeksWorking memoryBetter Corsi and multitasking scoresRCT
n 132 · 2020

Improved A single 1,290 mg dose, and to a greater extent 4 weeks of 430 mg or 1,290 mg/day, improved the Corsi Blocks working-memory task and a multitasking task versus placebo; the 860 mg dose showed no such benefit. After 4 weeks the highest dose lowered the skin-conductance response to a lab stressor. Mood was unaffected.

Design: RCT, n = 132, 2020
Population: Healthy UK adults aged 35-65
Form: Green oat herb extract (cognitaven)
Dose: 430, 860 or 1,290 mg/day
Duration: 29 days
Source: Reference 3 · PubMed 32485993 (opens PubMed)

Grade CCognition after 12 weeks in older adultsCognitionNo effectCrossover RCT
n 37 · 2012

No effect Daily supplementation did not affect any measure of cognition, tested at least 18 hours after the last dose.

Design: Crossover RCT, n = 37, 2012
Population: Healthy Australian adults averaging 67 years with normal cognition
Form: Wild green oat extract (Neuravena)
Dose: 1,500 mg/day
Duration: 12 weeks per period
Source: Reference 2 · PubMed 22690320 (opens PubMed)

Grade DAttention task speed and brain responses after a single doseAttentionFaster responsesRCT
n 20 · 2021

Improved Task performance was faster with no loss of accuracy after the extract, with smaller ERP components linked to performance monitoring; on placebo, speed and accuracy worsened.

Design: RCT, n = 20, 2021
Population: Healthy Spanish adults
Form: Wild green oat extract (Neuravena)
Dose: 800 mg, single dose
Duration: Single dose
Source: Reference 4 · PubMed 34658781 (opens PubMed)

What the numbers add up to

Each point is worked out from the data and the sources numbered on this page, with the arithmetic shown under it. It adds no new data and is not medical advice.

Timing of testing matters

Benefits showed up when tasks were measured hours after a dose, while the 12-week null trial tested people at least 18 hours after their last dose.^2,3,6

Studied doses

Doses used in research, shown against the official limits. They describe the studies, not a recommendation for you.

Studied doses in research, not advice. These are amounts used in research, not personal advice. Your clinician or pharmacist can say what fits you.

Doses studied in human trials

Doses studied in human trials ranged from 430 mg/day for 4 weeks to 1,500 mg/day for 12 weeks; single doses of 800-2,500 mg were tested in acute studies. These are research doses, not recommendations.^2,3,4,7,9

When trials measured an effect

3 outcomes

How long trials ran before effects were measured
Outcome	Measured at	Basis
Working memory and multitasking	After a single 1,290 mg dose; larger after 4 weeks of daily use	Cognitaven trial in 132 adults aged 35-65 (430 or 1,290 mg/day)³
Attention task speed	After a single 800 mg dose	Neuravena EEG trial in 20 adults⁴
Perceived stress and sleep quality in smokers cutting down	Week 8 (end of supplementation)	900 mg/day Neuravena versus placebo in 145 adults⁵

Interactions and safety

Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.

Interactions

0 agents

None found in our sources.

Check with what you take

Kept on this device only

Add what you take. We list every interaction our evidence profiles cite between Green Oat Extract and your picks, and between your picks.

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Most cited:

Add a supplement or medicine you take to check it against Green Oat Extract.

Starting from one medicine? The interaction checker rates how serious each pair is, on a curated list of 19 entries for 11 medicines. This cabinet has no severity rating: it lists every interaction row our supplement pages cite.

Who should be careful

6 groups

Oat allergy: The EU herbal monograph lists hypersensitivity to oat herb as a contraindication.⁸
Coeliac disease: The EU monograph advises caution in coeliac disease because data on the protein content of oat herb preparations are not available.⁸
Pregnancy and breastfeeding: Safety in pregnancy and breastfeeding has not been established, and the EU monograph does not recommend use in the absence of data.⁸
Children under 12: The EU monograph does not recommend oat herb for children under 12 because data are lacking.⁸
People taking sedatives: No interactions are reported in the final EU monograph, but oat herb is used traditionally for stress and sleep and has not been tested alongside sedative medicines.⁸
Driving and machinery: The EU herbal monograph warns that oat herb may impair the ability to drive and use machines; people affected should not drive or operate machinery.⁸

How to read the label

What to check on the Supplement Facts panel.

How to read the label

2 checks

Herb, not grain

Green oat extract is made from the green leaves and stems of the oat plant. It is not oat bran or oat beta-glucan, which come from the grain and are studied for cholesterol and blood sugar.^8,1

Branded extracts differ

The trials used specific branded extracts (Neuravena, cognitaven) at defined doses; generic oat straw or oat herb products are not standardized the same way.^3,5

Have the bottle? Photograph its Supplement Facts panel and see each line, green oat extract (oat herb) included, beside the doses and forms the trials used in Label X-Ray.

Frequently asked questions

Short answers to common questions; the numbers link to the sources below.

Common questions

6 answers

Does green oat extract improve focus or memory?

Small trials found single doses improved some attention and memory tasks, and one 4-week trial found working-memory gains. A 12-week trial in older adults found no effect, and most trials were industry-funded.^1,2,3

Does it help with stress or sleep?

In an 8-week trial in smokers cutting down, perceived stress and sleep quality improved more than on placebo. A 4-week trial found no mood effect. In the EU it is a traditional herbal medicine for mild stress and sleep, based on long-standing use.^5,3,8

Can green oat extract be taken long term?

It has not been studied beyond 12 weeks. The longest trial gave 1,500 mg/day for 12 weeks to older adults and found no cognitive benefit. The EU monograph advises seeing a doctor or qualified practitioner if symptoms persist during use.^2,8

What are the side effects of green oat extract?

Trials of up to 12 weeks found it well tolerated; in a 4-week trial, side effects were minor and no more frequent than on placebo. The EU monograph lists no known side effects but warns it may impair driving, lists oat hypersensitivity as a contraindication, and does not recommend it in pregnancy, breastfeeding or children under 12.^5,3,8

Is green oat extract the same as oatmeal or oat beta-glucan?

No. It is an extract of the green aerial parts of the oat plant, harvested before flowering. Oatmeal, oat bran and oat beta-glucan come from the grain and are a different product with different research.⁸

Is green oat extract gluten-free?

Not necessarily. The EU herbal monograph advises caution in coeliac disease because protein-content data for oat herb preparations are missing.⁸

Sources

9 sources: trial abstracts, NIH fact sheets and reference databases. Numbers in the text link here.

Sources cited on this page

9 sources

1Effect of Avena sativa (Oats) on cognitive function: A systematic review of randomized controlled trials.Systematic review Clin Nutr ESPEN, 2023 · PMID 36657906
2Chronic effects of a wild green oat extract supplementation on cognitive performance in older adults: a randomised, double-blind, placebo-controlled, crossover trial.Crossover RCT Nutrients, 2012 · PMID 22690320
3Acute and Chronic Effects of Green Oat (Avena sativa) Extract on Cognitive Function and Mood during a Laboratory Stressor in Healthy Adults: A Randomised, Double-Blind, Placebo-Controlled Study in Healthy Humans.RCT Nutrients, 2020 · PMID 32485993
4Effects of a Green Oat Herb Extract on Cognitive Performance and Neurophysiological Activity: A Randomized Double-Blind Placebo-Controlled Study.RCT Front Neurosci, 2021 · PMID 34658781
5Dietary supplementation with a wild green oat extract (Avena sativa L.) to improve wellness and wellbeing during smoking reduction or cessation: a randomized double-blind controlled study.RCT Front Nutr, 2024 · PMID 38962436
6Acute effects of a wild green-oat (Avena sativa) extract on cognitive function in middle-aged adults: A double-blind, placebo-controlled, within-subjects trial.Crossover RCT Nutr Neurosci, 2017 · PMID 26618715
7Acute effects of an Avena sativa herb extract on responses to the Stroop Color-Word test.Crossover RCT J Altern Complement Med, 2011 · PMID 21711204
8Community herbal monograph on Avena sativa L., herbaGuideline European Medicines Agency (HMPC), 2008 · ema.europa.eu
9Ingested oat herb extract (Avena sativa) changes EEG spectral frequencies in healthy subjects.Crossover RCT J Altern Complement Med, 2011 · PMID 21563962

What changed

Every dated change to this page: what changed, who made it and why.

Change log

3 entries

Dated changes to this page
Date	Change	Who and why
Oct 21, 2026FAQ, time to effect, questions, related	Re-checked against the 2023–2026 literature: a PubMed search for green oat, oat herb, Neuravena and cognitaven trials and meta-analyses found nothing newer than the 2024 smoking-reduction trial and the 2023 systematic review already in the table, so the evidence rows are unchanged. Checked LiverTox and LactMed (no entry for oat herb) and re-read the EU herbal monograph (interactions: none reported; undesirable effects: none known), so the interaction list stays empty. Replaced the FAQ item that duplicated the page's own 'What is' question with herb-versus-grain, rewrote the safety item as side effects, added long-term use, time-to-effect rows from the trial abstracts, page questions and goal-hub links.	Writer: Kymata Health EditorialTrigger: A–Z audit against docs/supplements/AUDIT-STANDARD.md
Oct 14, 2026all	Initial editorial evidence review (first draft). Every PMID checked against NCBI E-utilities esummary (titles and years taken from the record, none retracted) and the abstract read for each cited row. Studied doses are reported as research doses, not dosing advice.	Writer: Kymata Health EditorialTrigger: new page
Oct 14, 2026evidence	Independent adversarial review: industry count corrected to five cited trials (Dimpfel 2011 had two Frutarom Switzerland co-authors, per Crossref); EMA warning that oat herb may impair driving and machine use added; 860 mg arm null and 2,400 mg null noted; review wording kept to 'appeared to'; cognitaven tolerability taken from the full text.	Writer: Kymata Health EditorialTrigger: adversarial review

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