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Cognitive Decline

Cognitive decline refers to a naturally occurring reduction in cognition and memory formation associated with aging, and may be benign or associated with some disease states (such as Alzheimer's). Some supplements that are not inhernetly nootropic may reduce cognitive decline.

Research analysis led by Kamal Patel.
All content reviewed by the Examine.com Team. Published:
Last Updated:

Human Effect Matrix

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what supplements affect cognitive decline
Grade Level of Evidence
Robust research conducted with repeated double-blind clinical trials
Multiple studies where at least two are double-blind and placebo controlled
Single double-blind study or multiple cohort studies
Uncontrolled or observational studies only
Level of Evidence
? The amount of high quality evidence. The more evidence, the more we can trust the results.
Outcome Magnitude of effect
? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.
Consistency of research results
? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.
grade-a Ginkgo biloba Notable High See all 11 studies
For usage of EGb-761 at 240-360mg daily as a therapeutic option in people who already are experiencing cognitive decline, then it appears to be reliably effective and comparable to 10mg Donepezil.
grade-a Piracetam Notable Very High See all 6 studies
There appears to be a notable reduction in the rate of cognitive decline (or rehabiliation of aged cognition) associated with high dose Piracetam over time and in a general manner. Piracetam is sometimes used as a comparator for cognitive decline.
grade-b Oxiracetam Minor Very High See all 5 studies
Appears to reliably reduce the cognitive decline and related symptoms seen in dementia and other organic brain deterioration states, with particular efficacy towards verbal skill in doses above 1,200mg
grade-b Phosphatidylserine  
grade-c Alpha-GPC  
grade-c Blueberry  
grade-c CDP-choline  
grade-c Curcumin  
grade-c Dehydroepiandrosterone  
grade-c Eleutherococcus senticosus  
grade-c Fish Oil  
grade-c Polygala tenuifolia  
grade-c Polypodium leucotomos  
grade-c Yamabushitake  
grade-c DMAE  
grade-c Nitrate  
grade-c Vitamin E  
grade-d Panax ginseng  
grade-d Phenylpiracetam  
grade-d Vinpocetine  

All comparative evidence is now gathered in our ​A-to-Z Supplement Reference.

The evidence for each separate supplement is still freely available ​here.