Condition

Dementia

Dementia is a decline in memory and thinking that comes from damaged nerve cells, weaker chemical signaling between them, and reduced blood flow to brain tissue. Among supplements, oxiracetam has the strongest evidence, and small trials found thinking and memory decline improved, with limited evidence that alpha-GPC eased Alzheimer's symptoms. Most studies were small, and ginkgo biloba showed no clear difference in Alzheimer's risk in a large trial.

Sources: PMID 2521069; PMID 2781039; PMID 12637119

Updated 30 September 2026
How we grade
1 study cited
Dementia protocol

Supplements studied: 10
Graded outcomes: 10
Trials: 16
People studied: 7,469

Evidence by supplement

Strong
Moderate
Limited
Very limited

10 supplements

Oxiracetam

Oxiracetam: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People
	Cognitive Decline Small Improvement	Improves (the measure goes down)	Small effect	4 studies	415 people
Studies that measured cognitive decline Oxiracetam in the treatment of multi-infarct dementia and primary degenerative dementiaJ Neuropsychiatry Clin Neurosci · PMID 2521069 Oxiracetam in the treatment of multi-infarct dementiaProg Neuropsychopharmacol Biol Psychiatry · PMID 2781039 Oxiracetam in dementia: a double-blind, placebo-controlled studyActa Neurol Scand · PMID 1414239 and 1 more on the Oxiracetam page
	Functionality in Elderly or Injured No effect		NoneNo effect		73 people
	Memory	Improves (the measure goes up)			272 people
	Quality of Life	Improves (the measure goes up)			58 people
	Verbal Fluency	Improves (the measure goes up)			131 people

Alpha-GPC

Alpha-GPC: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People
	Alzheimer's Disease Symptoms Moderate Improvement	Improves (the measure goes down)	Moderate effect	1 study	261 people
Studies that measured alzheimer's disease symptoms Cognitive improvement in mild to moderate Alzheimer's dementia after treatment with the acetylcholine precursor choline alfoscerate: a multicenter, double-blind, randomized, placebo-controlled trialClin Ther · PMID 12637119
	Cognitive Decline	Improves (the measure goes down)			261 people

Phlebodium aureum

Cerebral Blood Flow: improves
Cognitive Decline: improves

Phlebodium aureum: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People
	Cerebral Blood Flow Small Increase	Improves (the measure goes up)	Small effect	1 study	45 people
Studies that measured cerebral blood flow Double-blind, randomized, placebo-controlled pilot study with anapsos in senile dementia: effects on cognition, brain bioelectrical activity and cerebral hemodynamicsMethods Find Exp Clin Pharmacol · PMID 11196347
	Cognitive Decline	Improves (the measure goes down)			45 people

Kanna

Cognition: improves
Sleep Quality: improves
Executive Function: improves

Kanna: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People
	Cognition Small Improvement	Improves (the measure goes up)	Small effect		16 people
	Sleep Quality	Improves (the measure goes up)		1 study	16 people
Studies that measured sleep quality Proof-of-Concept Randomized Controlled Study of Cognition Effects of the Proprietary Extract Sceletium tortuosum (Zembrin) Targeting Phosphodiesterase-4 in Cognitively Healthy Subjects: Implications for Alzheimer's DementiaEvid Based Complement Alternat Med · PMID 25389443
	Executive Function	Improves (the measure goes up)			16 people
	Memory	Improves (the measure goes up)			16 people
	Reaction Time	Improves (the measure goes up)			16 people
	Subjective Well-Being	Improves (the measure goes up)			16 people

Aniracetam

Emotional State: improves
Functionality: improves

Aniracetam: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Emotional State Significantly improved emotional state at 3 months	Improves (the measure goes up)	Moderate effect		276 people
	Functionality Improved functionality at 3 months vs cholinesterase inhibitors	Improves (the measure goes up)	Small effect		276 people

Vitamin E

Alzheimer's Disease Risk
Cognition: improves

Vitamin E: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People
	Alzheimer's Disease Risk No effect		NoneNo effect	3 studies	820 people
Studies that measured alzheimer's disease risk Effects of vitamin E supplementation on the risk and progression of AD: a systematic review and meta-analysis.Nutr Neurosci · PMID 30900960 Vitamin E and donepezil for the treatment of mild cognitive impairmentN Engl J Med · PMID 15829527 Vitamin E for Alzheimer's dementia and mild cognitive impairment.Cochrane Database Syst Rev · PMID 28418065
	Cognition	Improves (the measure goes up)			820 people

Ginkgo Biloba

Alzheimer's Disease Risk
Cognitive Decline: improves
Memory: improves

Ginkgo Biloba: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People
	Alzheimer's Disease Risk No effect		NoneNo effect	1 study	6,138 people
Studies that measured alzheimer's disease risk Ginkgo biloba for prevention of dementia: a randomized controlled trialJAMA · PMID 19017911
	Cognitive Decline	Improves (the measure goes down)		9 studies	1,209 people
Studies that measured cognitive decline Efficacy and tolerability of a once daily formulation of Ginkgo biloba extract EGb 761® in Alzheimer's disease and vascular dementia: results from a randomised controlled trialPharmacopsychiatry · PMID 22086747 Ginkgo biloba special extract in dementia with neuropsychiatric features. A randomised, placebo-controlled, double-blind clinical trialArzneimittelforschung · PMID 17341003 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 dementiaPharmacopsychiatry · PMID 8741021 and 6 more on the Ginkgo Biloba page
	Memory	Improves (the measure goes up)		3 studies	236 people
Studies that measured memory Acute cognitive effects of standardised Ginkgo biloba extract complexed with phosphatidylserineHum Psychopharmacol · PMID 17457961 A double-blind, placebo-controlled, randomized trial of Ginkgo biloba extract EGb 761 in a sample of cognitively intact older adults: neuropsychological findingsHum Psychopharmacol · PMID 12404671 Safety and effectiveness of a traditional ginkgo fresh plant extract - results from a clinical trialForsch Komplementmed · PMID 19657199
	Tinnitus Symptoms	Improves (the measure goes down)		3 studies	371 people
Studies that measured tinnitus symptoms Clonazepam quiets tinnitus: a randomised crossover study with Ginkgo bilobaJ Neurol Neurosurg Psychiatry · PMID 22626945 Ginkgo biloba for tinnitusCochrane Database Syst Rev · PMID 23543524 Effectiveness of Ginkgo biloba in treating tinnitus: double blind, placebo controlled trialBMJ · PMID 11154618
	Cerebral Blood Flow	Improves (the measure goes up)		1 study	80 people
Studies that measured cerebral blood flow Effects of Ginkgo biloba on cerebral blood flow assessed by quantitative MR perfusion imaging: a pilot studyNeuroradiology · PMID 21061003
	Subjective Well-Being	Improves (the measure goes up)		1 study	371 people
	Alzheimer's Disease Symptoms	Improves (the measure goes down)			1,129 people

Piracetam

Cognition
Cognitive Decline: improves

Piracetam: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People
	Cognition No effect		NoneNo effect	1 study	24 people
Studies that measured cognition Neuropsychological changes in demented patients treated with acetyl-L-carnitineInt J Clin Pharmacol Res · PMID 2387665
	Cognitive Decline	Improves (the measure goes down)		5 studies	1,488 people
Studies that measured cognitive decline [On the dose-effect relationship in the therapy with piracetam (author's transl)]Arzneimittelforschung · PMID 786310 Drug therapy and memory training programs: a double-blind randomized trial of general practice patients with age-associated memory impairmentInt Psychogeriatr · PMID 7865703 Clinical efficacy of piracetam in cognitive impairment: a meta-analysisDement Geriatr Cogn Disord · PMID 12006732 and 2 more on the Piracetam page

Phosphatidylserine

Cognitive Decline: improves

Phosphatidylserine: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Cognitive Decline	Improves (the measure goes down)		2 studies	33 people
Studies that measured cognitive decline Double-blind cross-over study of phosphatidylserine vs. placebo in patients with early dementia of the Alzheimer typeEur Neuropsychopharmacol · PMID 1633433 Effects of phosphatidylserine in Alzheimer's diseasePsychopharmacol Bull · PMID 1609044

Alpha-Lipoic Acid

Dementia Symptoms: changes; see studies

Alpha-Lipoic Acid: outcomes studied for Dementia
Grade	Outcome	Effect	Size	Studies	People	Studies list
	Dementia Symptoms	Changes; see studies		1 study	53 people
Studies that measured dementia symptoms Down syndrome and dementia: a randomized, controlled trial of antioxidant supplementationAm J Med Genet A · PMID 21739598

Key findings

Cognitive DeclineOxiracetamImproves (the measure goes down)
Alzheimer's Disease SymptomsAlpha-GPCImproves (the measure goes down)
Cerebral Blood FlowPhlebodium aureumImproves (the measure goes up)

The Dementia & Cognitive Decline protocol

2 primary supplements · 4 supporting supplements

Omega-3 DHA1,000–2,000 mg DHA daily
Phosphatidylserine300 mg daily

See the full protocol

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Support alongside medical care. These supplements are not a treatment for Dementia. If you are being treated for it, talk to your clinician before adding one: supplements can interact with medicines.

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Studies cited

1 study from PubMed

Effectiveness of non-pharmacological therapies on cognitive function in patients with dementia-A network meta-analysis of randomized controlled trials.Front Aging Neurosci · PMID 36967820

Evidence by supplement

Key findings

The Dementia & Cognitive Decline protocol

Shop the evidence-backed picks

Studies cited

Related conditions

Supplement stack for Dementia