Vitamin B6
Pyridoxine, a B vitamin
A B vitamin found in foods such as poultry, fish, oats and bananas, sold in supplements mostly as pyridoxine, and also called pyridoxal phosphate or pyridoxamine. This page covers only studies in people that measured thinking, memory, mood, stress, sleep, energy, tiredness or quality of life, not all research on vitamin B6. In those, it is studied mostly for mood and thinking, often in people with a health condition. Here is every one we could find, sorted from each study's summary.
- Common form: pyridoxine
- Most tested: 100 mg a day
- Often taken daily for weeks
From every paper to the studies that matter
Our search looked only at vitamin B6 papers on thinking, mood, sleep and energy, not at all research on the vitamin. Many of those are case reports, lab work or papers that only measure B6 in the blood. A smaller share gives vitamin B6 to people, and that is what this page is about.
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1,779 papers on vitamin B6 and thinking, mood, sleep or energy.Every record in PubMed, all years
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240 are about people.The rest: 400 lab and animal studies, 325 reviews, 814 on chemistry, farming and more
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44 give vitamin B6 on its own.91 more give it in a blend, such as with magnesium, other B vitamins or a multivitamin
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23 are randomised against a placebo.Randomised controlled trials In a randomised controlled trial, people are put into groups by chance, one taking the treatment and one a placebo or other comparison. Chance spreads differences such as age and health evenly, so a difference between the groups is more likely to be down to the treatment., the strongest kind of study
Bar lengths use a square-root scale so the small numbers stay visible.
How much research there is
- 44 studies giving vitamin B6 to people
- 23 of them randomised against a placebo A placebo-controlled trial compares a real treatment with a dummy that looks the same, the placebo. People often feel better when they expect to, so comparing against a placebo shows how much of the change comes from the treatment itself.
- 3,994 people taking part, where studies say
- 63 systematic reviews A systematic review searches for every study on a question in a set, written-down way, judges the quality of each and sums up what they show together. Many include a meta-analysis. The Atlas lists these as pooled reviews. pooling the trials
Studies in people, by year published
Vitamin B6 on its own. Vitamin B6 added to a medicine or usual care and compared with that care alone counts as on its own.
What the studies looked at
Each study can measure several things. Choose a topic to see its studies in the list below.
Studies in people with a diagnosed condition are counted here and listed with their population. We describe what they measured, not what they might treat. Most studies also report safety; see below.
What was tested, and how much
Doses here are milligrams of vitamin B6 a day, as the summaries give them. Most studies used pyridoxine, but a few state the weight of the salt, pyridoxine hydrochloride, which holds somewhat less vitamin itself, and some do not name the form. Doses range from a few milligrams to several hundred, and many are far above the amount in an ordinary diet. Some studies gave a single dose or a few days of treatment, and others ran for months.
Daily amount, one dot per study
Studies per extract
Named extracts are the maker's brand. "Not named" means the study didn't say.
All studies in people
Filter the list, then open a study on PubMed. Each row comes from the study's published summary, and most follow people with a health condition, such as epilepsy treated with medicines, restless legs, bipolar disorder or the menopause, rather than healthy adults.
| Study | Who took part | People | Extract and daily dose | Length |
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| Field 2026RCT, placebo | Adults from general population, mostly female | 267 | Pyridoxine, 100 mg | 4 weeks |
| Dhivya 2025RCT, active or other control | Post-menopausal women with mild cognitive impairment | 180 | Pyridoxine, 25 mg | 26 weeks |
| Zandifar 2024RCT, placebo | Hospitalised bipolar-I patients in mania on lithium | 66 | Pyridoxine, 40 mg | 8 weeks |
| Falsaperla 2024Observational | Neonatal and infant cases of pyridoxine-dependent epilepsy | 55 | Pyridoxine | – |
| C Curtin 2023Crossover, placebo | Healthy college women using oral contraceptives | 8 | Pyridoxine, 100 mg | 12 weeks |
| Field 2022RCT, placebo | Young adults | 478 | Pyridoxine | 4 weeks |
| Lob 2022Observational | Children with epilepsy on levetiracetam | 240 | Pyridoxine | – |
| Ghavidel-Parsa 2022RCT, placebo | Patients with fibromyalgia | 90 | Pyridoxine, 80 mg | – |
| Jadidi 2022RCT, placebo | Patients with restless legs syndrome | 75 | Pyridoxine, 40 mg | 9 weeks |
| Tseng 2022Observational | Siblings with pyridoxine-dependent epilepsy | 37 | Pyridoxine | – |
| Zhuo 2021RCT, active or other control | Men with treatment-resistant schizophrenia and hyperprolactinemia | 200 | Pyridoxine, 600 mg | 16 weeks |
| Khodadad 2021RCT, placebo | Pregnant women at risk of postpartum depression | 81 | Pyridoxine, 80 mg | 6 weeks |
| Charalambous 2021RCT, placebo | Cancer patients with hand-foot syndrome | 54 | PyridoxineOn the skin | 6 weeks |
| Badrfam 2021RCT, placebo | Patients with bipolar-I mania on lithium | 50 | Pyridoxine, 80 mg | 8 weeks |
| García-García 2021Crossover, placebo | Healthy adults | 47 | Pyridoxine, 100 mg | 4 weeks |
| Dreischmeier 2021Observational | Veterans with epilepsy on levetiracetam | – | Pyridoxine | – |
| Chelban 2019Single-arm or open-label | Axonal polyneuropathy patients with PDXK mutations | 5 | Pyridoxal 5'-phosphate | 52 weeks |
| Pouteau 2018RCT, active or other control | Stressed adults with low magnesium | 264 | Magne B6, 30 mg | 8 weeks |
| Adventure-Heart 2018RCT, placebo | Adults, dream and sleep study | 100 | Pyridoxine, 240 mg | 1 weeks |
| de Rooy 2018Observational | Late-onset pyridoxine-dependent epilepsy patients | 4 | Pyridoxine | – |
| Marino 2018RCT, active or other control | Children on levetiracetam with behavioural side effects | – | Pyridoxine | – |
| Riikonen 2015Observational | Children with pyridoxine-responsive infantile epilepsy | 6 | Pyridoxine, 150 mg | – |
| Var 2014Non-randomised controlled | Women using oral contraception, rural Cambodia | 1,011 | Not named | – |
| Stott 2005RCT, placebo | Older adults with vascular disease | 185 | Pyridoxine, 25 mg | 52 weeks |
| Bryan 2002RCT, placebo | Healthy women of various ages | 211 | Pyridoxine, 75 mg | 5 weeks |
| Lerner 2002Crossover, placebo | Schizophrenia and schizoaffective patients | 15 | Pyridoxine, 400 mg | 9 weeks |
| Ebben 2002Crossover, placebo | College students | 12 | Pyridoxine, 250 mg | 1 weeks |
| Luboshitzky 2002Crossover, placebo | Healthy men | 12 | Pyridoxine, 100 mg | – |
| Shiloh 2001Single-arm or open-label | Schizophrenia patients with minor depression | 9 | Pyridoxine, 150 mg | 4 weeks |
| Villegas-Salas 1997RCT, placebo | Women starting oral contraceptives | 124 | Pyridoxine, 150 mg | 4 weeks |
| Mabin 1995RCT, placebo | Children with atopic dermatitis | 48 | Pyridoxine hydrochloride, 50 mg | 4 weeks |
| Bartel 1994Crossover, placebo | Healthy young adults given theophylline | 20 | Pyridoxine | – |
| Deijen 1992RCT, placebo | Healthy older men | 76 | Pyridoxine hydrochloride, 20 mg | 13 weeks |
| Doll 1989Crossover, placebo | Women with premenstrual syndrome | 63 | Pyridoxine, 50 mg | 26 weeks |
| Tolonen 1988Non-randomised controlled | Elderly adults | – | Pyridoxine hydrochloride, 2 mg | 52 weeks |
| Kendall 1987RCT, placebo | Women with premenstrual mood changes | 55 | Pyridoxine, 150 mg | 9 weeks |
| Malmgren 1987Crossover, placebo | Women with premenstrual tension syndrome | 19 | Pyridoxine | – |
| Barletta 1984Single-arm or open-label | Ten healthy women | 10 | Pyridoxine, 600 mg | – |
| Hallert 1983Single-arm or open-label | Adults with coeliac disease | 12 | Pyridoxine, 80 mg | 26 weeks |
| Casacchia 1982Other | Depressed men and controls | 10 | Pyridoxine, 300 mg | – |
| Pueschel 1980Non-randomised controlled | Infants with Down syndrome | 89 | Pyridoxine hydrochloride | – |
| Bukreev 1978Single-arm or open-label | Patients with involutional depression or late-onset psychosis | 48 | Pyridoxine | – |
| Adams 1974Other | Women using oral contraceptives with depression | – | Pyridoxine | – |
| Adams 1973Non-randomised controlled | Women with depression on oral contraceptives | – | Pyridoxine hydrochloride | – |
What's known about safety
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In trials
We haven't read these studies in full for side effects, so this page cannot give a trial-based safety picture yet. The studies we list used doses from about 2 to 600 mg a day. Case reports in our search describe nerve damage after heavy use of vitamin B6 supplements.
Dose range from this page's study list (summaries only); case reports in the evidence library, Oct 2026
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In the UK
Pyridoxine hydrochloride, pyridoxine 5'-phosphate and pyridoxal 5'-phosphate are permitted forms in food supplements. The Department of Health and Social Care advises no more than 10 mg a day of vitamin B6 in supplements unless a doctor advises it. Pyridoxamine is not on the permitted list we opened.
Directive 2002/46/EC Annex II as retained in UK law (legislation.gov.uk); NHS vitamins and minerals, B vitamins and folic acid, Oct 2026
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Check first
The NHS says that 200 mg or more a day can lead to a loss of feeling in the arms and legs (peripheral neuropathy), which usually improves after stopping but in a few cases has been permanent. It says the effect of doses between 10 mg and 200 mg is unclear. Speak to a pharmacist or doctor first if you take other medicines, are pregnant or are breastfeeding, as we found no UK guidance on those.
NHS vitamins and minerals, B vitamins and folic acid, Oct 2026
Where these studies come from
We list every published study in people that gave vitamin B6 and measured thinking, memory, mood, stress, sleep, energy, tiredness or quality of life, as pyridoxine, pyridoxal 5'-phosphate or pyridoxamine. Vitamin B6 added to a medicine or usual care counts as on its own; vitamin B6 given with magnesium, with doxylamine, or with other vitamins and nutrients counts as a blend. Studies that only measured vitamin B6 in the blood or diet are left out, as are vitamin B6 given only to a control group or as background to a different test. This first version is built from each study's summary; full-paper checks come next.
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We search
PubMed, the world's main library of medical research, for every paper on L-theanine.
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We keep studies in people
Lab and animal work is counted but left out of the list, because it doesn't tell you what happens in people.
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We note the basics
Who took part, how many, how much and for how long, from each study's published summary. A second check corrects what the first read gets wrong.
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We read them in full
Results appear once we've read the whole paper and checked every number. The date at the top shows when this entry was last updated.
Download the study list
Every study in people as a spreadsheet, 44 rows, free to reuse with a link back.
Versions
Each update to the data gets a new version number, so you can tell what changed and when.
See every version
1.0 · 24 Oct 2026. First release. Every published study giving vitamin B6 to people that measured thinking, memory, mood, stress, sleep, energy or quality of life is listed from its summary. None is read in full yet.
