Mental Focus title image

Mental Focus

Mental & Cognitive Health

Mental focus makes it easier to give a task your attention, follow information, and return to the work after a distraction. It can involve a brief period of sharp alertness or the steadier concentration needed for reading, study, and detailed work. Knowing which kind of attention you need makes support more relevant. Several connected factors contribute to a focused state. Wakefulness helps you engage with a task, a settled mind makes competing demands easier to manage, and normal brain nutrition supports the processes behind attention and thinking. Ingredients used for alertness, relaxed attention, and cognitive nutrition address different parts of that picture. Useful progress is visible in how the task goes. Staying with a piece of work, following a discussion more comfortably, or recovering your train of thought can be more informative than a strong feeling of stimulation. The aim is clear, sustained engagement that fits the demands of your day.

Warnings

  • Count all stimulants: Count caffeine from drinks and supplements together. Review intake if you notice jitteriness, palpitations, anxiety, or disrupted sleep.
  • Check medicine interactions: Ask a pharmacist or clinician to review your exact products alongside your medicines. The ingredient, amount, and treatment determine which combinations are suitable.
  • Review potent cognitive ingredients: Review compounds such as huperzine and vinpocetine individually for suitability and interactions. Agree any ongoing use with an appropriately qualified professional.
  • Use iron for a clear need: Use an appropriate assessment to guide iron supplementation. Tiredness or hair changes can have several causes, and excess iron can be harmful.
Ingredient overview

Goal guidance

Lifestyle changes

Create focused work periods with clear priorities and manageable breaks. Reduce avoidable distractions and protect the sleep that makes concentration easier the following day.

Diet changes

Eat regularly and stay comfortably hydrated during mentally demanding work. Choose caffeine timing and amounts that fit your sensitivity and bedtime.

Who this is for

Adults looking for support with concentration during work, study, or other mentally demanding activities.

Who should be careful

Review stimulant use with anxiety, palpitations, high blood pressure, or sleep problems. Check combinations with ADHD treatments and other nervous-system medicines, particularly when using potent nootropic ingredients.

Expected timeline

Alertness ingredients can act within the same day, while nutritional and routine changes need more consistent use. Judge progress by the task itself, including sustained attention and ease of returning after a distraction.

Common mistakes

Increasing stimulation can make you feel busier without improving concentration. Protect sleep, reduce avoidable distractions, and choose a manageable amount of support.

Ingredients

Choline Vitamins
Impact
Highest effect
Typical dose250–1000 mg / day
Choline is an essential building block for the neurotransmitter acetylcholine and for the structural integrity of brain cell membranes (phosphatidylcholine). Adequate choline intake is critical for baseline cognitive processing, and supplementation can help ensure the brain has sufficient resources for demanding mental tasks.

Study evidence

22 studies

The evidence does not show that Choline reliably improves everyday mental focus. Attention benefits appear in selected research on citicoline or early development, but ordinary choline supplementation and reviews in cognitively impaired adults have also produced no clear attention benefit.

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Folate Vitamins
Impact
Highest effect
Typical dose400–800 mcg / day
Folate (as methylfolate) is a critical component of the one-carbon metabolism cycle, which is directly involved in producing the methyl donors required for neurotransmitter synthesis. Deficiencies in folate can impair this process, leading to low mood and poor concentration.

Study evidence

12 studies

Folate may improve selected cognitive abilities in certain older adults or people with low folate, but it is not established as a general focus enhancer. Direct attention-related research is mixed, and nutritional status, vitamin B12 status and the population studied matter.

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Magnesium Minerals
Impact
Highest effect
Typical dose200–400 mg / day
Magnesium acts as a gatekeeper for NMDA receptors, which are involved in learning and memory. It also plays a vital role in ATP production for cellular energy and helps maintain healthy nerve signaling, contributing to mental clarity and reducing brain fog.

Study evidence

6 studies

Magnesium shows some promise for attention and cognitive performance, but a reliable improvement in everyday focus has not been established. Findings in people with sleep or cognitive difficulties may not extend to healthy adults seeking better concentration.

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Vitamin B12 Vitamins
Impact
Highest effect
Typical dose250–1000 mcg / day
As part of the B-complex family, B12 is vital for maintaining the myelin sheath that protects nerve fibers, ensuring rapid communication between brain cells. Deficiency can lead to significant cognitive impairment, fatigue, and poor concentration.

Study evidence

11 studies

Vitamin B12 deficiency can impair attention and thinking, but extra B12 has not been established as a focus enhancer when levels are adequate. Favorable findings often come from people with cognitive impairment or from multivitamin products, which do not isolate B12’s effect.

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Vitamin B6 Vitamins
Impact
Highest effect
Typical dose10–50 mg / day
Vitamin B6 (as P-5-P) is required for the conversion of amino acid precursors (like L-Tyrosine) into neurotransmitters that govern alertness, motivation, and concentration. Without adequate B6, the brain cannot efficiently produce these essential chemicals, leading to impaired focus and mental fatigue.

Study evidence

6 studies

Vitamin B6 has not consistently improved mental focus when tested on its own. Some research reports memory benefits or better performance with nutrient blends, but these findings do not establish that a standalone B6 supplement improves everyday attention or concentration.

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Vitamin D Vitamins
Impact
Highest effect
Typical dose1000–5000 IU / day
Vitamin D receptors are widespread throughout the brain in areas critical for cognition. Adequate levels are crucial for dopamine synthesis and neuroprotection, while deficiency is strongly linked to brain fog, poor executive function, and difficulty concentrating. Correcting deficiency can lead to significant improvements in mental clarity.

Study evidence

11 studies

Vitamin D has not shown a consistent benefit for mental focus in generally healthy people. Some evidence suggests improved attention symptoms in children with ADHD, especially with low vitamin D status, but this mainly concerns supplementation alongside treatment and remains uncertain.

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Studies

Explore published research for this goal.

Sources

Up to five highest-ranked published examples per ingredient. Study counts and charts include all published studies for the connection.

  1. Four-year follow-up of a randomized controlled trial of choline for neurodevelopment in fetal alcohol spectrum disorder.
    Wozniak JR; Fink BA; Fuglestad AJ; Eckerle JK; Boys CJ; Sandness KE; Radke JP; Miller NC; Lindgren C; Brearley AM; Zeisel SH; Georgieff MK · Journal of neurodevelopmental disorders · 2021
    Randomized trial31 participantsCholine
  2. The relation of dietary choline to cognitive performance and white-matter hyperintensity in the Framingham Offspring Cohort.
    Poly C; Massaro JM; Seshadri S; Wolf PA; Cho E; Krall E; Jacques PF; Au R · The American journal of clinical nutrition · 2012
    Cohort study1,391 participantsCholine
  3. Association between Maternal Choline, Fetal Brain Development, and Child Neurocognition: Systematic Review and Meta-Analysis of Human Studies.
    Obeid R; Derbyshire E; Schön C · Advances in nutrition (Bethesda, Md.) · 2022
    Meta-analysis30 studies pooledCholine
  4. Effect of Choline Supplementation on Neurological, Cognitive, and Behavioral Outcomes in Offspring Arising from Alcohol Exposure During Development: A Quantitative Systematic Review of Clinical and Preclinical Studies.
    Akison LK; Kuo J; Reid N; Boyd RN; Moritz KM · Alcoholism, clinical and experimental research · 2019
    Systematic reviewCholine
  5. Perinatal choline effects on neonatal pathophysiology related to later schizophrenia risk.
    Ross RG; Hunter SK; McCarthy L; Beuler J; Hutchison AK; Wagner BD; Leonard S; Stevens KE; Freedman R · The American journal of psychiatry · 2013
    Randomized trialCholine
  6. Folate and long-chain polyunsaturated fatty acid supplementation during pregnancy has long-term effects on the attention system of 8.5-y-old offspring: a randomized controlled trial.
    Catena A; Muñoz-Machicao JA; Torres-Espínola FJ; Martínez-Zaldívar C; Diaz-Piedra C; Gil A; Haile G; Györei E; Molloy AM; Decsi T; Koletzko B; Campoy C · The American journal of clinical nutrition · 2016
    Randomized trial136 participantsFolate
  7. Cerebral folate receptor autoantibodies in autism spectrum disorder.
    Frye RE; Sequeira JM; Quadros EV; James SJ; Rossignol DA · Molecular psychiatry · 2014
    Non-randomized trial93 participantsFolate
  8. Folate, vitamin B-12, and cognitive function in the Boston Puerto Rican Health Study.
    Boumenna T; Scott TM; Lee JS; Palacios N; Tucker KL · The American journal of clinical nutrition · 2026
    Cross-sectional study1,408 participantsFolate
  9. Vitamins B9 and B12 in children with attention deficit hyperactivity disorder (ADHD).
    Razavinia F; Ebrahimiyan A; Faal Siahkal S; Ghazinezhad N; Abedi P · International journal for vitamin and nutrition research. Internationale Zeitschrift fur Vitamin- und Ernahrungsforschung. Journal international de vitaminologie et de nutrition · 2024
    Meta-analysis982 participants6 studies pooledFolate
  10. Does L-Methylfolate Supplement Methylphenidate Pharmacotherapy in Attention-Deficit/Hyperactivity Disorder?: Evidence of Lack of Benefit From a Double-Blind, Placebo-Controlled, Randomized Clinical Trial.
    Surman C; Ceranoglu A; Vaudreuil C; Albright B; Uchida M; Yule A; Spencer A; Boland H; Grossman R; Rhodewalt L; Fitzgerald M; Biederman J · Journal of clinical psychopharmacology · 2019
    Randomized trial44 participantsFolate
  11. Relationship between Whole-Blood Magnesium and Cognitive Performance among Chinese Adults.
    Lu Z; He R; Zhang Y; Li B; Li F; Fu Y; Rong S · Nutrients · 2023
    Cross-sectional study1,006 participantsMagnesium
  12. Serum Magnesium and Cognitive Function Among Qatari Adults.
    Al-Ghazali K; Eltayeb S; Musleh A; Al-Abdi T; Ganji V; Shi Z · Frontiers in aging neuroscience · 2020
    Cross-sectional study1,000 participantsMagnesium
  13. Magnesium status and attention deficit hyperactivity disorder (ADHD): A meta-analysis.
    Effatpanah M; Rezaei M; Effatpanah H; Effatpanah Z; Varkaneh HK; Mousavi SM; Fatahi S; Rinaldi G; Hashemi R · Psychiatry research · 2019
    Meta-analysisMagnesium
  14. The effect of vitamin D and magnesium supplementation on the mental health status of attention-deficit hyperactive children: a randomized controlled trial.
    Hemamy M; Pahlavani N; Amanollahi A; Islam SMS; McVicar J; Askari G; Malekahmadi M · BMC pediatrics · 2021
    Randomized trial33 participantsMagnesium
  15. The effects of magnesium L-threonate (Magtein®) on cognitive performance and sleep quality in adults: a randomised, double-blind, placebo-controlled trial.
    Lopresti AL; Smith SJ · Frontiers in nutrition · 2026
    Randomized trial100 participantsMagnesium
  16. Vitamin B12 supplementation improves cognitive function in middle aged and elderly patients with cognitive impairment.
    Zhou L; Bai X; Huang J; Tan Y; Yang Q · Nutricion hospitalaria · 2023
    Randomized trial115 participantsVitamin B12
  17. Associations of one-carbon metabolism, related B-vitamins and ApoE genotype with cognitive function in older adults: identification of a novel gene-nutrient interaction.
    Gordon S; Hoey L; McNulty H; Keenan J; Pangilinan F; Brody LC; Ward M; Strain JJ; McAnena L; McCann A; Molloy AM; Cunningham C; McCarroll K; Hughes CF · BMC medicine · 2025
    Observational study4,553 participantsVitamin B12
  18. Vitamin B12 Levels Association with Functional and Structural Biomarkers of Central Nervous System Injury in Older Adults.
    Beaudry-Richard A; Abdelhak A; Saloner R; Sacco S; Montes SC; Oertel FC; Cordano C; Jabassini N; Ananth K; Gomez A; Keihani A; Chapman M; Javvadi S; Saha S; Staffaroni A; Songster C; Warren M; Boscardin JW; Kramer J; Miller B; Miller JW; Green R; Green AJ · Annals of neurology · 2025
    Cross-sectional study231 participantsVitamin B12
  19. Cobalamin: a critical vitamin in the elderly.
    Wolters M; Ströhle A; Hahn A · Preventive medicine · 2005
    Narrative reviewVitamin B12
  20. The association of betaine, homocysteine and related metabolites with cognitive function in Dutch elderly people.
    Eussen SJ; Ueland PM; Clarke R; Blom HJ; Hoefnagels WH; van Staveren WA; de Groot LC · The British journal of nutrition · 2007
    Randomized trial195 participantsVitamin B12
  21. Vitamin B-6 supplementation in elderly men: effects on mood, memory, performance and mental effort.
    Deijen JB; van der Beek EJ; Orlebeke JF; van den Berg H · Psychopharmacology · 1995
    Randomized trial76 participantsVitamin B6
  22. The effect of vitamin B6 on cognition.
    Malouf R; Grimley Evans J · The Cochrane database of systematic reviews · 2004
    Systematic review109 participants2 studies pooledVitamin B6
  23. Antiemetic use during pregnancy and child neurodevelopment: population-based birth cohort study.
    Cho Y; Choi EY; Han JY; Kim H; Choe YJ; Shin JY · BMC medicine · 2025
    Cohort study630,904 participantsVitamin B6
  24. A nutritional blend of taurine, vitamins B6, B9, and B12 improves motivated behaviors in healthy adults-a double-blinded randomized clinical trial.
    Anlacan VM; Jamora RDG; Krattinger LF; De Longis E; Hartweg M; Steinmann M; Trovò L · Frontiers in nutrition · 2026
    Randomized trial44 participantsVitamin B6
  25. B-Vitamin Therapy for Kidney Transplant Recipients Lowers Homocysteine and Improves Selective Cognitive Outcomes in the Randomized FAVORIT Ancillary Cognitive Trial
    Tammy M Scott, Graham Rogers, Daniel E Weiner, Kathryn Livingston, Jacob Selhub, Paul F Jacques, Irwin H Rosenberg, Aron M Troen · The Journal of Prevention of Alzheimer's Disease · 2017
    Randomized trial584 participantsVitamin B6
  26. Three Doses of Vitamin D and Cognitive Outcomes in Older Women: A Double-Blind Randomized Controlled Trial.
    Castle M; Fiedler N; Pop LC; Schneider SJ; Schlussel Y; Sukumar D; Hao L; Shapses SA · The journals of gerontology. Series A, Biological sciences and medical sciences · 2021
    Randomized trialVitamin D
  27. Vitamin D and executive function: a preliminary report.
    Hansen AL; Dahl L; Bakke L; Thayer JF · Perceptual and motor skills · 2012
    Cross-sectional study25 participantsVitamin D
  28. Effects of Vitamin D Supplementation on Cognitive Function in Older Adults: A Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Methodology-Assessed Systematic Review and Meta-Analysis of Randomized Clinical Trials.
    Behrouzi R; Shahinfar H; Jazayeri S · Nutrition reviews · 2026
    Meta-analysis9 studies pooledVitamin D
  29. Maternal vitamin D concentrations are associated with faster childhood reaction time and response speed, but not with motor fluency and flexibility, at the age of 5-6 years: the Amsterdam Born Children and their Development (ABCD) Study.
    Brouwer-Brolsma EM; Vrijkotte TGM; Feskens EJM · The British journal of nutrition · 2019
    Cohort study1,854 participantsVitamin D
  30. Serum 25-hydroxyvitamin D and cognitive decline in the very old: the Newcastle 85+ Study.
    Granic A; Hill TR; Kirkwood TB; Davies K; Collerton J; Martin-Ruiz C; von Zglinicki T; Saxby BK; Wesnes KA; Collerton D; Mathers JC; Jagger C · European journal of neurology · 2015
    Cohort study775 participantsVitamin D
  31. Acetyl-L-carnitine in the treatment of mildly demented elderly patients.
    Passeri M; Cucinotta D; Bonati PA; Iannuccelli M; Parnetti L; Senin U · International journal of clinical pharmacology research · 1990
    Randomized trial60 participantsAcetyl L-Carnitine
  32. Acetyl-L-Carnitine Supplementation During HCV Therapy With Pegylated Interferon-α 2b Plus Ribavirin: Effect on Work Performance; A Randomized Clinical Trial.
    Malaguarnera G; Pennisi M; Gagliano C; Vacante M; Malaguarnera M; Salomone S; Drago F; Bertino G; Caraci F; Nunnari G; Malaguarnera M · Hepatitis monthly · 2014
    Randomized trial62 participantsAcetyl L-Carnitine
  33. [Psycho-functional changes in attention and learning under the action of L-acetylcarnitine in 17 young subjects. A pilot study of its use in mental deterioration].
    Lino A; Boccia MM; Rusconi AC; Bellomonte L; Cocuroccia B · La Clinica terapeutica · 1992
    Non-randomized trial17 participantsAcetyl L-Carnitine
  34. Acetyl-L-carnitine (ALC) in attention-deficit/hyperactivity disorder: a multi-site, placebo-controlled pilot trial.
    Arnold LE; Amato A; Bozzolo H; Hollway J; Cook A; Ramadan Y; Crowl L; Zhang D; Thompson S; Testa G; Kliewer V; Wigal T; McBurnett K; Manos M · Journal of child and adolescent psychopharmacology · 2008
    Randomized trial112 participantsAcetyl L-Carnitine
  35. Acetyl-L-carnitine for patients with hepatic encephalopathy.
    Martí-Carvajal AJ; Gluud C; Arevalo-Rodriguez I; Martí-Amarista CE · The Cochrane database of systematic reviews · 2019
    Meta-analysis398 participants5 studies pooledAcetyl L-Carnitine
  36. Acute Alpha-Glycerylphosphorylcholine Supplementation Enhances Cognitive Performance in Healthy Men.
    Kerksick CM · Nutrients · 2024
    Randomized trial20 participantsAlpha-GPC
  37. Effects of modafinil and caffeine on night-time vigilance of air force crewmembers: A randomized controlled trial.
    Wingelaar-Jagt YQ; Bottenheft C; Riedel WJ; Ramaekers JG · Journal of psychopharmacology (Oxford, England) · 2023
    Randomized trial32 participantsCaffeine
  38. Acute effects of caffeine on attention: a comparison of non-consumers and withdrawn consumers.
    Smith AP; Christopher G; Sutherland D · Journal of psychopharmacology (Oxford, England) · 2013
    Randomized trial70 participantsCaffeine
  39. Performance and alertness effects of caffeine, dextroamphetamine, and modafinil during sleep deprivation.
    Wesensten NJ; Killgore WD; Balkin TJ · Journal of sleep research · 2006
    Randomized trial48 participantsCaffeine
  40. Effects of caffeine on mood and performance: a study of realistic consumption.
    Brice CF; Smith AP · Psychopharmacology · 2003
    Clinical trial24 participantsCaffeine
  41. Effects of caffeine or diphenhydramine on visual vigilance.
    Fine BJ; Kobrick JL; Lieberman HR; Marlowe B; Riley RH; Tharion WJ · Psychopharmacology · 1995
    Randomized trial24 participantsCaffeine
  42. The Effects of 8-Week Creatine Hydrochloride and Creatine Ethyl Ester Supplementation on Cognition, Clinical Outcomes, and Brain Creatine Levels in Perimenopausal and Menopausal Women (CONCRET-MENOPA): A Randomized Controlled Trial.
    Korovljev D; Ostojic J; Panic J; Ranisavljev M; Todorovic N; Nedeljkovic D; Kuzmanovic J; Vranes M; Stajer V; Ostojic SM · Journal of the American Nutrition Association · 2026
    Randomized trial36 participantsCreatine
  43. Creatine and Cognition in Aging: A Systematic Review of Evidence in Older Adults.
    Marshall S; Kitzan A; Wright J; Bocicariu L; Nagamatsu LS · Nutrition reviews · 2026
    Systematic review1,542 participants6 studies pooledCreatine
  44. Effect of creatine supplementation and sleep deprivation, with mild exercise, on cognitive and psychomotor performance, mood state, and plasma concentrations of catecholamines and cortisol.
    McMorris T; Harris RC; Swain J; Corbett J; Collard K; Dyson RJ; Dye L; Hodgson C; Draper N · Psychopharmacology · 2006
    Clinical trial19 participantsCreatine
  45. Six-Week Supplementation with Creatine in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): A Magnetic Resonance Spectroscopy Feasibility Study at 3 Tesla.
    Godlewska BR; Sylvester AL; Emir UE; Sharpley AL; Clarke WT; Martens MAG; Cowen PJ · Nutrients · 2024
    Single-arm trial14 participantsCreatine
  46. The effects of creatine supplementation on cognitive function in adults: a systematic review and meta-analysis.
    Xu C; Bi S; Zhang W; Luo L · Frontiers in nutrition · 2026
    Meta-analysis492 participants16 studies pooledCreatine
  47. The effectiveness and efficacy of Rhodiola rosea L.: a systematic review of randomized clinical trials.
    Hung SK; Perry R; Ernst E · Phytomedicine : international journal of phytotherapy and phytopharmacology · 2012
    Systematic review11 studies pooledRhodiola
  48. Effects of Rhodiola rosea on Physical and Decision-Making Performance in Football Players: A Randomised Controlled Trial.
    Dou Y; Wang Y; Zhang W; Jiang Y; Zhang J; Yang T; Han Z; Li Y; Liu C; Ren D · Nutrients · 2026
    Randomized trial24 participantsRhodiola
  49. Dose-Response Effects of Short-Term Rhodiola rosea (Golden Root Extract) Supplementation on Anaerobic Exercise Performance and Cognitive Function in Resistance-Trained Athletes: A Randomized, Crossover, Double-Blind, and Placebo-Controlled Study.
    Koozehchian MS; Newton AT; Mabrey G; Bonness FM; Rafajlovska R; Naderi A · Nutrients · 2025
    Randomized trial27 participantsRhodiola
  50. Effects of Rhodiola rosea supplementation on mental performance, physical capacity, and oxidative stress biomarkers in healthy men.
    Jówko E; Sadowski J; Długołęcka B; Gierczuk D; Opaszowski B; Cieśliński I · Journal of sport and health science · 2022
    Randomized trial26 participantsRhodiola
  51. Evidence-based efficacy of adaptogens in fatigue, and molecular mechanisms related to their stress-protective activity.
    Panossian A; Wikman G · Current clinical pharmacology · 2009
    Narrative reviewEleutheroRhodiola
  52. Effects of Tea (Camellia sinensis) or its Bioactive Compounds l-Theanine or l-Theanine plus Caffeine on Cognition, Sleep, and Mood in Healthy Participants: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
    Payne ER; Aceves-Martins M; Dubost J; Greyling A; de Roos B · Nutrition reviews · 2025
    Meta-analysis50 studies pooledTheanine
  53. Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study.
    Baba Y; Inagaki S; Nakagawa S; Kaneko T; Kobayashi M; Takihara T · Journal of medicinal food · 2021
    Randomized trialTheanine
  54. Acute effects of theanine, caffeine and theanine-caffeine combination on attention.
    Kahathuduwa CN; Dassanayake TL; Amarakoon AMT; Weerasinghe VS · Nutritional neuroscience · 2018
    Clinical trial20 participantsTheanine
  55. Safety and Efficacy of AlphaWave® L-Theanine Supplementation for 28 Days in Healthy Adults with Moderate Stress: A Randomized, Double-Blind, Placebo-Controlled Trial.
    Moulin M; Crowley DC; Xiong L; Guthrie N; Lewis ED · Neurology and therapy · 2024
    Randomized trial30 participantsTheanine
  56. Effect of L-theanine on selective attention in a traffic-related reaction task in sleep-deprived young adults: a double-blind placebo-controlled, crossover study.
    Karunaratne UW; Dassanayake TL · Nutritional neuroscience · 2025
    Randomized trial24 participantsTheanine
  57. Efficacy and safety of ashwagandha root extract in children and adolescents with mild attention-deficit/hyperactivity disorder: a randomized, double-blind, placebo-controlled trial.
    Naik S; Muralidhar G; Rao BS; Agarwal S; Jain M · Journal of medicine and life · 2026
    Randomized trial58 participantsAshwagandha
  58. Efficacy and Safety of Ashwagandha (Withania somnifera (L.) Dunal) Root Extract in Improving Memory and Cognitive Functions.
    Choudhary D; Bhattacharyya S; Bose S · Journal of dietary supplements · 2018
    Randomized trial50 participantsAshwagandha
  59. Effect of ashwagandha (Withania somnifera) extract with Sominone (Somin-On™) to improve memory in adults with mild cognitive impairment: A randomized, double-blind, placebo-controlled study.
    Rai HP; Mishra DN · Journal of psychopharmacology (Oxford, England) · 2025
    Randomized trial40 participantsAshwagandha
  60. A clinical assessment of the therapeutic effects of Ashwagandha root extract on cognitive performance, sleep, and fatigue in children aged 6-12 years.
    Saxena A; Lopresti A; Sharif M; Elon N; Suri R; Langade DK · Frontiers in nutrition · 2026
    Randomized trial85 participantsAshwagandha
  61. A standardized Ashwagandha root extract alleviates stress, anxiety, and improves quality of life in healthy adults by modulating stress hormones: Results from a randomized, double-blind, placebo-controlled study.
    Majeed M; Nagabhushanam K; Mundkur L · Medicine · 2023
    Randomized trial54 participantsAshwagandha
  62. Evaluating the effects of Bacopa monnieri on cognitive performance and sleep quality of patients with mild cognitive impairment: A triple-blinded, randomized, placebo-controlled trial.
    Delfan M; Kordestani-Moghaddam P; Gholami M; Kazemi K; Mohammadi R · Explore (New York, N.Y.) · 2024
    Randomized trial62 participantsBacopa
  63. Comparative effects of Bacopa monnieri and Ginkgo biloba on cognitive functions: A systematic review and network meta-analysis.
    Tiemtad P; Ingkaninan K; Temkitthawon P; Thimkorn P; Rattanachaisit N; Teaktong T; Dhippayom T · Phytomedicine : international journal of phytotherapy and phytopharmacology · 2026
    Meta-analysis2,107 participants29 studies pooledBacopa
  64. Cognitive effects of two nutraceuticals Ginseng and Bacopa benchmarked against modafinil: a review and comparison of effect sizes.
    Neale C; Camfield D; Reay J; Stough C; Scholey A · British journal of clinical pharmacology · 2013
    Systematic reviewBacopa
  65. Efficiency of Different Supplements in Alleviating Symptoms of ADHD with or Without the Use of Stimulants: A Systematic Review.
    Al Shahab S; Al Balushi R; Qambar A; Abdulla R; Qader M; Abdulla S; Jahrami H · Nutrients · 2025
    Systematic reviewBacopa
  66. Meta-analysis of randomized controlled trials on cognitive effects of Bacopa monnieri extract.
    Kongkeaw C; Dilokthornsakul P; Thanarangsarit P; Limpeanchob N; Norman Scholfield C · Journal of ethnopharmacology · 2014
    Meta-analysis518 participants9 studies pooledBacopa
  67. Stimulating effect of adaptogens: an overview with particular reference to their efficacy following single dose administration.
    Panossian A; Wagner H · Phytotherapy research : PTR · 2005
    Narrative reviewEleuthero
  68. No benefit adding eleutherococcus senticosus to stress management training in stress-related fatigue/weakness, impaired work or concentration, a randomized controlled study.
    Schaffler K; Wolf OT; Burkart M · Pharmacopsychiatry · 2014
    Randomized trial144 participantsEleuthero
  69. The influence of n-3 polyunsaturated fatty acids on cognitive function in individuals without dementia: a systematic review and dose-response meta-analysis.
    Suh SW; Lim E; Burm SY; Lee H; Bae JB; Han JW; Kim KW · BMC medicine · 2024
    Meta-analysis9,660 participants24 studies pooledEPA (Eicosapentaenoic Acid)
  70. EPA supplementation improves teacher-rated behaviour and oppositional symptoms in children with ADHD.
    Gustafsson PA; Birberg-Thornberg U; Duchén K; Landgren M; Malmberg K; Pelling H; Strandvik B; Karlsson T · Acta paediatrica (Oslo, Norway : 1992) · 2011
    Randomized trial92 participantsEPA (Eicosapentaenoic Acid)
  71. Docosahexaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA)-Should They Be Mandatory Supplements in Pregnancy?
    Amza M; Haj Hamoud B; Sima RM; Dinu MD; Gorecki GP; Popescu M; Gică N; Poenaru MO; Pleș L · Biomedicines · 2024
    Narrative reviewEPA (Eicosapentaenoic Acid)
  72. Supplementation with oil rich in eicosapentaenoic acid, but not in docosahexaenoic acid, improves global cognitive function in healthy, young adults: results from randomized controlled trials.
    Patan MJ; Kennedy DO; Husberg C; Hustvedt SO; Calder PC; Khan J; Forster J; Jackson PA · The American journal of clinical nutrition · 2021
    Randomized trial310 participantsEPA (Eicosapentaenoic Acid)
  73. Ginkgo biloba Extract EGb 761 in the Treatment of Patients with Mild Neurocognitive Impairment: A Systematic Review.
    Hort J; Duning T; Hoerr R · Neuropsychiatric disease and treatment · 2023
    Systematic review946 participants9 studies pooledGinkgo
  74. Proof of efficacy of the Ginkgo biloba special extract EGb 761 in outpatients suffering from mild to moderate primary degenerative dementia of the Alzheimer type or multi-infarct dementia.
    Kanowski S; Herrmann WM; Stephan K; Wierich W; Hörr R · Phytomedicine : international journal of phytotherapy and phytopharmacology · 2012
    Randomized trial216 participantsGinkgo
  75. Proof of efficacy of the ginkgo biloba special extract EGb 761 in outpatients suffering from mild to moderate primary degenerative dementia of the Alzheimer type or multi-infarct dementia.
    Kanowski S; Herrmann WM; Stephan K; Wierich W; Hörr R · Pharmacopsychiatry · 1996
    Randomized trial216 participantsGinkgo
  76. Ginkgo biloba extract improved cognitive and neurological functions of acute ischaemic stroke: a randomised controlled trial.
    Li S; Zhang X; Fang Q; Zhou J; Zhang M; Wang H; Chen Y; Xu B; Wu Y; Qian L; Xu Y · Stroke and vascular neurology · 2021
    Randomized trial348 participantsGinkgo
  77. Ginkgo biloba in the Aging Process: A Narrative Review.
    Barbalho SM; Direito R; Laurindo LF; Marton LT; Guiguer EL; Goulart RA; Tofano RJ; Carvalho ACA; Flato UAP; Capelluppi Tofano VA; Detregiachi CRP; Bueno PCS; Girio RSJ; Araújo AC · Antioxidants (Basel, Switzerland) · 2024
    Narrative review14 studies pooledGinkgo
  78. Acute effects of a standardised extract of Hericium erinaceus (Lion's Mane mushroom) on cognition and mood in healthy younger adults: a double-blind randomised placebo-controlled study.
    Surendran G; Saye J; Binti Mohd Jalil S; Spreadborough J; Duong K; Shatwan IM; Lilley D; Heinrich M; Dodd GF; Surendran S · Frontiers in nutrition · 2025
    Randomized trial18 participantsHericium mushroom
  79. Effect of vinpocetine (cognitol™) on cognitive performances of a nigerian population.
    Ogunrin A · Annals of medical and health sciences research · 2014
    Non-randomized trial112 participantsVinpocetine
  80. "Brain-specific" nutrients: a memory cure?
    McDaniel MA; Maier SF; Einstein GO · Nutrition (Burbank, Los Angeles County, Calif.) · 2004
    Narrative reviewVinpocetine
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    Subhan Z; Hindmarch I · European journal of clinical pharmacology · 1985
    Randomized trial12 participantsVinpocetine
  82. Iodine supplementation improves cognition in iodine-deficient schoolchildren in Albania: a randomized, controlled, double-blind study.
    Zimmermann MB; Connolly K; Bozo M; Bridson J; Rohner F; Grimci L · The American journal of clinical nutrition · 2006
    Randomized trial310 participantsIodine
  83. Iodine intake from supplements and diet during pregnancy and child cognitive and motor development: the INMA Mother and Child Cohort Study.
    Murcia M; Espada M; Julvez J; Llop S; Lopez-Espinosa MJ; Vioque J; Basterrechea M; Riaño I; González L; Alvarez-Pedrerol M; Tardón A; Ibarluzea J; Rebagliato M · Journal of epidemiology and community health · 2019
    Cohort study1,803 participantsIodine
  84. Breastfeeding and maternal and infant iodine nutrition.
    Azizi F; Smyth P · Clinical endocrinology · 2009
    Systematic review36 studies pooledIodine
  85. Preconception Maternal Iodine Status Is Positively Associated with IQ but Not with Measures of Executive Function in Childhood.
    Robinson SM; Crozier SR; Miles EA; Gale CR; Calder PC; Cooper C; Inskip HM; Godfrey KM · The Journal of nutrition · 2019
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  86. Iodine deficiency: consequences and progress toward elimination.
    Maberly GF; Haxton DP; van der Haar F · Food and nutrition bulletin · 2006
    Narrative reviewIodine
  87. The Effect of Iron-Fortified Lentils on Blood and Cognitive Status among Adolescent Girls in Bangladesh.
    Barnett AL; Wenger MJ; Yunus FM; Jalal C; DellaValle DM · Nutrients · 2023
    Randomized trial359 participantsIron
  88. Cognitive Performance in Indian School-Going Adolescents Is Positively Affected by Consumption of Iron-Biofortified Pearl Millet: A 6-Month Randomized Controlled Efficacy Trial.
    Scott SP; Murray-Kolb LE; Wenger MJ; Udipi SA; Ghugre PS; Boy E; Haas JD · The Journal of nutrition · 2019
    Randomized trial140 participantsIron
  89. Effects of iron supplementation twice a week on attention score and haematologic measures in female high school students.
    Rezaeian A; Ghayour-Mobarhan M; Mazloum SR; Yavari M; Jafari SA · Singapore medical journal · 2015
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  90. Randomised study of cognitive effects of iron supplementation in non-anaemic iron-deficient adolescent girls.
    Bruner AB; Joffe A; Duggan AK; Casella JF; Brandt J · Lancet (London, England) · 1996
    Randomized trial81 participantsIron
  91. Effect of iron supplementation on cognition in Greek preschoolers.
    Metallinos-Katsaras E; Valassi-Adam E; Dewey KG; Lönnerdal B; Stamoulakatou A; Pollitt E · European journal of clinical nutrition · 2005
    Randomized trial49 participantsIron
  92. Cognition after a 4-week high phenylalanine intake in adults with phenylketonuria - a randomized controlled trial.
    Trepp R; Muri R; Maissen-Abgottspon S; Haynes AG; Hochuli M; Everts R · The American journal of clinical nutrition · 2024
    Randomized trial30 participantsPhenylalanine
  93. A systematic review of cognitive functioning in early treated adults with phenylketonuria.
    Hofman DL; Champ CL; Lawton CL; Henderson M; Dye L · Orphanet journal of rare diseases · 2019
    Systematic review16 studies pooledPhenylalanine
  94. Are Functional Brain Networks Sensitive to High Phenylalanine in Adults With Phenylketonuria?
    Vallesi V; Morishima Y; Winiger L; Trepp R; Everts R; Muri R · JIMD reports · 2026
    Randomized trial23 participantsPhenylalanine
  95. Sustained attention in untreated non-PKU-hyperphenylalaninemia.
    Weglage J; Schmidt E; Fünders B; Pietsch M; Ullrich K · Journal of clinical and experimental neuropsychology · 1997
    Case-control study48 participantsPhenylalanine
  96. Effects of L-histidine depletion and L-tyrosine/L-phenylalanine depletion on sensory and motor processes in healthy volunteers.
    van Ruitenbeek P; Sambeth A; Vermeeren A; Young SN; Riedel WJ · British journal of pharmacology · 2009
    Clinical trial17 participantsPhenylalanine
  97. The efficacy of zinc augmentation in children with attention deficit hyperactivity disorder under treatment with methylphenidate: A randomized controlled trial.
    Noorazar SG; Malek A; Aghaei SM; Yasamineh N; Kalejahi P · Asian journal of psychiatry · 2021
    Randomized trial60 participantsZinc
  98. Effects of zinc supplementation on parent and teacher behaviour rating scores in low socioeconomic level Turkish primary school children.
    Uçkardeş Y; Ozmert EN; Unal F; Yurdakök K · Acta paediatrica (Oslo, Norway : 1992) · 2009
    Randomized trial226 participantsZinc
  99. The Role of Iron and Zinc in the Treatment of ADHD among Children and Adolescents: A Systematic Review of Randomized Clinical Trials.
    Granero R; Pardo-Garrido A; Carpio-Toro IL; Ramírez-Coronel AA; Martínez-Suárez PC; Reivan-Ortiz GG · Nutrients · 2021
    Systematic review9 studies pooledZinc
  100. Does zinc moderate essential fatty acid and amphetamine treatment of attention-deficit/hyperactivity disorder?
    Arnold LE; Pinkham SM; Votolato N · Journal of child and adolescent psychopharmacology · 2001
    Randomized trialZinc
  101. The effect of zinc supplementation in children with attention deficit hyperactivity disorder: A systematic review and dose-response meta‑analysis of randomized clinical trials.
    Talebi S; Miraghajani M; Ghavami A; Mohammadi H · Critical reviews in food science and nutrition · 2022
    Meta-analysis489 participants6 studies pooledZinc