Vitamins & Supplements · Supplement formula
Multi-Ingredient Brain Formulas
Multi-ingredient brain formulas (nootropic blends) · also called Brain formulas, nootropic blends and stacks, memory supplements, fórmulas para el cerebro, suplementos para la memoria
Brain formulas are supplements that mix several ingredients, such as caffeine, L-theanine, bacopa, ginkgo, citicoline and B vitamins, and are sold for memory, focus and mental energy. Only three small trials of finished blends were found, and none shows a blend beats its separate ingredients. Single-ingredient evidence is mostly low and cannot be added up. Lab checks have found missing and unlabelled ingredients, including hidden stimulants.
General information, not medical advice. Last substantive update · Not medically reviewed. A named clinician has not signed off on this page. How this page is made
About Multi-Ingredient Brain Formulas
Brain formulas mix several ingredients for memory and focus. Few finished blends have been tested, and results come mostly from single ingredients, so they cannot be added up. Labels can be wrong, and some products hold hidden stimulants.
What this kind of product is
A brain formula, or nootropic blend, is a supplement that mixes several ingredients and is sold for memory, focus and mental energy. It comes as capsules, tablets, powders, drinks or gummies.
A review of 103 memory supplements in US pharmacies and grocery stores found each one held at least one of 18 common ingredients. A survey of 152 active adults found caffeine, creatine, DHA, L-theanine and ashwagandha were the nootropics they named most.
What is usually inside
Common ingredients include caffeine and L-theanine (see the caffeine and theanine pages), bacopa, ginkgo, citicoline and alpha-GPC, phosphatidylserine, creatine, omega-3 fish oil, B vitamins, vitamin E and herbs such as ashwagandha and lion's mane. Many also add a multivitamin.
Each of these has its own page, linked under Related. Trial results for one ingredient apply to that ingredient, at the amount and form tested, not to a blend that contains it.
Who they are sold to
Makers target students, older adults worried about memory, gamers, athletes and, in one lab study, US service members who asked about such products. The global brain-health supplement market was valued at about US$7.6 billion in 2021, according to a 2023 review.
Reading the label
In the US, the Supplement Facts label must show serving size, servings per container, and each ingredient with its amount per serving. The FDA does not approve supplements or their labels before sale.
A "proprietary blend" is listed by name with its total weight, and its ingredients in order of weight, so you may not see the amount of each. Ingredients without a set Daily Value are marked "Daily Value Not Established". Differences in how capsules, powders and gummies are made were not researched here.
What the research shows
Three small trials tested finished blends and gave mixed, short-lived results. For single ingredients, caffeine and L-theanine show small short-term attention gains, bacopa and ashwagandha small memory gains, and ginkgo, omega-3 and vitamin E mostly no benefit for dementia aims.
No study read showed a blend beats its separate ingredients. A 2021 review called the evidence low certainty and inconsistent.
At a glance
Traditional uses history, not proof
- Many single ingredients come from tea, coffee, Ayurvedic and other herbal traditions
- Sold as modern memory, focus and energy products
Studied for research
- Finished blends, very low certainty
- Short-term attention from caffeine and L-theanine, low certainty
- Memory from bacopa, ashwagandha and creatine, low certainty
- Dementia prevention with ginkgo, omega-3 or vitamin E, mostly no benefit
- Multivitamins and memory in older adults, low certainty
- Blends beating single ingredients, insufficient evidence
Main compounds
- Caffeine
- L-theanine
- Bacopa and ashwagandha extracts
- Ginkgo
- Citicoline, alpha-GPC and phosphatidylserine
- Creatine
- B vitamins, vitamin E and omega-3
Common forms
- Capsules and tablets
- Powders and drinks
- Gummies
- Proprietary blends and multi-ingredient "stacks"
Research links: 2023 review: over-the-counter memory supplements (103 products) · 2020 lab check: brain-health supplement labels · 2023 trial: ten-herb supplement in older adults · 2021 review: nine ingredients for healthy adults · NCCIH: supplements and cognitive function · Research Library · Genes & Biomarkers Library
What it is and its history
- Accepted scientific name
- Multi-ingredient brain formulas (nootropic blends, memory supplements)
- Common names
- Brain formulas (English); Nootropic blends (English); Memory supplements (English); Nootropic stacks (English); Fórmulas para el cerebro (Spanish); Suplementos para la memoria (Spanish); Nootrópicos (Spanish)
- Family or group
- A product type. A supplement that mixes several ingredients (herbs, amino acids, vitamins, minerals, choline compounds, caffeine) and is sold for memory, focus or mental energy.
- Harvest and processing
- Made by mixing extracts, powders and purified compounds into capsules, tablets, powders, drinks or gummies. Details of manufacture were not read from a source.
- Look-alikes and adulterants
- Name: Caffeine plus L-theanine; Note: A two-ingredient pairing with its own page.; Name: Multivitamins; Note: A vitamin and mineral mix; has its own page.; Name: Energy drinks and pre-workouts; Note: Caffeine-based drinks and powders; not researched here.; Name: Prescription medicines for ADHD or dementia; Note: Regulated drugs, not supplements.
- Sustainability and conservation
- Not assessed.
What is inside, and how it may work
What it contains and how those compounds act in cells and animals. Laboratory and animal mechanisms are not proven effects in people.
Main compounds
| Compound | Family | Where it is concentrated | Activity studied | Level of evidence |
|---|---|---|---|---|
| Caffeine | stimulant | Not read from a source. | The most steady short-term attention result of the usual ingredients; most often named in a survey of active adults (21.7%). 12 18 | Human data |
| L-theanine | amino acid from tea | Not read from a source. | Single servings shortened choice reaction time in a 31-trial review. 7 16 19 | Human data |
| Bacopa (Bacopa monnieri) extract | herb extract | Not read from a source. | Faster reaction times and some free-recall gains in trials of 12 weeks or more. 9 17 | Human data |
| Ashwagandha and rhodiola extracts | adaptogen herb extracts | Not read from a source. | Memory, attention and executive-function gains reported for ashwagandha. 26 31 | Human data |
| Ginkgo (Ginkgo biloba) extract | herb extract | Not read from a source. | No lower dementia rate in a large trial; bleeding concern. 6 23 | Human data |
| Citicoline, alpha-GPC and phosphatidylserine | choline compounds and a phospholipid | Not read from a source. | Citicoline: positive but poor-quality trials. Alpha-GPC: stroke association. Phosphatidylserine: not supported in mental disorders. 2 11 10 | Human data |
| Creatine | amino-acid derivative | Not read from a source. | Better memory scores in older adults in a pooled review. 20 | Human data |
| Lion's mane (Hericium erinaceus) | mushroom | Not read from a source. | A few small human trials; many lab results. 14 | Human and lab |
| Apoaequorin | protein | Not read from a source. | One 90-day trial in adults with memory concerns. 15 | Human data |
| B vitamins, vitamin E, omega-3 | vitamins and fats | Not read from a source. | NCCIH: no convincing benefit for dementia aims, with mixed B-vitamin results. 30 | Human (reviews) |
Mechanisms, receptors and pathways
| Target or pathway | Gene or receptor | What was found | Level |
|---|---|---|---|
| Finished blends | Not specified | No study read measured how a finished blend acts in the body, apart from urine and gut-bacteria markers in one 90-day herb trial. Mechanisms are the separate ingredients' and are not established for blends. 24 | Not established |
| Choline compounds as acetylcholine precursors | Acetylcholine; trimethylamine-N-oxide (TMAO) gut metabolite | The alpha-GPC cohort paper says alpha-GPC is used for its possible role as an acetylcholine precursor, and that choline has been linked with higher cardiovascular risk via TMAO. This is a proposed pathway, not shown here. 11 | Proposed |
| Apoaequorin and calcium in nerve cells | Intracellular calcium | The trial abstract says lab studies showed apoaequorin regulates calcium in nerve cells. This is lab-based background, not shown in the trial. 15 | Lab (as described in a trial abstract) |
Absorption, metabolism and elimination
- Absorption
- Not found for blends.
- Distribution
- Not found.
- Metabolism
- Not found.
- Elimination
- Not found.
- Bioavailability
- Not compared across blends in the sources read.
Isolated compounds versus whole extracts
Blends are processed mixes of extracts and isolated compounds. Foods that supply the same nutrients bring other nutrients and different amounts. No trial comparing a blend with the foods was read.
Nutritional composition
No USDA or NIH amounts for food sources of blend ingredients are stated here. Food sources of individual nutrients are on their own pages.
1 mixed findings4 low certainty1 very low certainty2 not enough evidence
What was looked at
The 8 benefits and uses checked for Multi-Ingredient Brain Formulas, each with how strong the evidence is. Tap one to open it.
- Trials of finished brain blendsVery low certainty
- Short-term attention from caffeine and L-theanineLow certainty
- Memory from bacopa, ashwagandha and other herbsLow certainty
- Memory from creatineLow certainty
- Lion's mane and apoaequorinNot enough evidence
- Preventing or slowing dementia: ginkgo, citicoline, vitamin E, omega-3 and B vitaminsMixed findings
- Multivitamins and memory in older adultsLow certainty
- Do blends beat their single ingredients?Not enough evidence
Lab markers tracked in the studies
Choice reaction timeTask speed and working memory on computer testsNew dementiaMemory test scores
What is Multi-Ingredient Brain Formulas good for?
What research found for finished brain blends and for their usual ingredients, and how strong the evidence is. Evidence for one ingredient does not carry over to a blend.
Benefits, one by one
Each card is a research question, not a promise. Tap a goal to filter. Open a card to see the studies, doses and limits.
Trials of finished brain blends
Very low certaintyOnly a few small trials have tested a finished brain blend. Two tested a single serving and one tested ten herbs for 90 days. Some tests got faster, but one trial saw worse memory scores, and the maker paid for it. These trials cannot say which ingredient did the work or whether any blend beats its single ingredients.
3 studiesEach trial tested a different product. Amounts are in the studies tab…
Studies, doses and limits
What the trials found
A 90-day trial in 128 adults aged 55 to 75 with noticed memory decline tested a ten-herb product. Task speed improved on some computer tests, memory scores were worse, and the authors say uneven groups made this hard to read. A single-serving crossover trial in 26 young adults found faster responses on several tests 30 minutes later. A single-serving trial in 40 adults of bacopa, American ginseng and coffee-fruit extract found better working-memory accuracy 45 minutes later.
Results
Mixed and thin. Some speed gains with single servings. No sign that blends help memory over time.
Effect sizes as reported
Effect sizes about 0.4 to 0.6 in the 26-person trial. No sizes in the 128-person abstract.
Why this rating
Very low because there are three small trials, each of a different product, two of them one-serving only, one paid for by the maker, and the ingredient lists are partly missing.
Form and dose studied
Each trial tested a different product. Amounts are in the studies table.
Who was studied
Healthy adults aged 18 to 60 in two trials; adults aged 55 to 75 with noticed memory decline in the third.
Limits
No trial compared a blend with its separate ingredients. The coffee-fruit and caffeine-like ingredients in some blends may explain the faster results.
Why researchers looked
Companies sell blends, so researchers have tested a few of the actual products to see whether the mix does anything.
Traditional use
Brain formulas are modern products. Their single ingredients come from many sources: tea, coffee, Ayurvedic and Chinese herbs, mushrooms, and the diet.
Proposed mechanism Not established
Not established. None of the three trials measured how a blend acts in the body, except that one looked at urine and gut-bacteria markers.
A proposed mechanism does not show that the effect happens in people.
Not reported in the three abstracts. See the Safety tab for label problems.
Short-term attention from caffeine and L-theanine
Low certaintyCaffeine and L-theanine are the ingredients with the most steady short-term attention results. A pooled review found a single serving of L-theanine speeded choice reaction time. Caffeine plus L-theanine showed small gains in the first two hours, with wide uncertainty. These trials tested the ingredients alone, not finished blends.
4 studiesStudied as single servings. Amounts are in the studies table.
Studies, doses and limits
What the trials found
A 2026 review of 31 trials (1,168 people) found a single serving of L-theanine shortened choice reaction time (SMD 0.51), while the stress result was modest and came mostly from weaker studies. A 2025 review of five trials in 148 healthy adults found one attention measure improved by about 15 ms, but not simple reaction time or the Stroop test. A 2025 review of 50 trials (15 pooled) found small differences for theanine plus caffeine in the first two hours, with confidence intervals that often crossed zero. A 2023 review of plant nootropics said caffeine enhances attention and executive function.
Results
Small, short-lived gains on lab attention tasks in healthy adults. Not everyday performance.
Effect sizes as reported
Choice reaction time SMD 0.51 (L-theanine); attention switching accuracy SMD 0.33 (theanine plus caffeine, hour 2).
Why this rating
Low because gains are small, last about two hours, are measured on lab tasks, and vary between reviews. The tea-company funding of one review and a supplement-company founder on another are noted.
Form and dose studied
Studied as single servings. Amounts are in the studies table.
Who was studied
Healthy adults.
Limits
Short lab tasks are not daily performance. Confidence intervals often cross zero. Blends were not tested in these reviews.
Why researchers looked
Caffeine and L-theanine are the best-known pairing, and many brain formulas contain both.
Traditional use
Brain formulas are modern products. Their single ingredients come from many sources: tea, coffee, Ayurvedic and Chinese herbs, mushrooms, and the diet.
Proposed mechanism Not established
Not established in the sources read.
A proposed mechanism does not show that the effect happens in people.
No serious adverse events were reported in the 31-trial review. See the Safety tab for caffeine cautions.
Memory from bacopa, ashwagandha and other herbs
Low certaintyReviews of single herb extracts found small gains. Bacopa taken for at least 12 weeks shortened some reaction times and improved free recall on some tests. A 2026 review of 20 trials found ashwagandha improved memory, attention and executive function. Rhodiola results are mixed and not separated in the review. These tested single extracts, not blends.
4 studiesBacopa extracts were taken for 12 weeks or longer in the reviews. Amo…
Studies, doses and limits
What the trials found
A 2014 pooled review of nine bacopa trials (518 people, 12 weeks or longer) found shorter Trail B and choice reaction times. A 2012 review of six trials found better free recall on 9 of 17 tests and little elsewhere. A 2026 meta-analysis of 20 ashwagandha trials (1,249 people) found better memory (SMD 0.52), attention (0.29) and executive function. A 2026 review of 24 trials, five of them rhodiola, said benefits were reported but pointed to short trials and small samples.
Results
Modest gains in single-extract trials, with differences between extracts and tests.
Effect sizes as reported
Ashwagandha memory SMD 0.52; bacopa Trail B -17.9 (units as printed in the abstract).
Why this rating
Low because trials are short, use different extracts and tests, and the reviews pool small studies. Results for the herbs alone do not carry over to a blend.
Form and dose studied
Bacopa extracts were taken for 12 weeks or longer in the reviews. Amounts are in the studies table.
Who was studied
Mostly healthy adults; some trials in adults with stress or memory complaints.
Limits
Standardized extracts, not unspecified amounts in a blend. Rhodiola cognition was not separated in the abstract.
Why researchers looked
Bacopa, ashwagandha and rhodiola come from traditional medicine and are common in memory formulas.
Traditional use
Brain formulas are modern products. Their single ingredients come from many sources: tea, coffee, Ayurvedic and Chinese herbs, mushrooms, and the diet.
Proposed mechanism Not established
Not established in the sources read.
A proposed mechanism does not show that the effect happens in people.
Not covered in the abstracts. See the Safety tab for medicine cautions.
Memory from creatine
Low certaintyA 2023 pooled review of eight trials found creatine improved memory test scores overall, with a clear gain in older adults (66 to 76) and none in younger people. Creatine appears in some brain formulas.
1 studiesStudied in many amounts across trials; see the studies table.
Studies, doses and limits
What the trials found
The review pooled eight randomised trials in healthy people. Overall SMD 0.29; older adults 0.88; younger people 0.03. Differences between trials were large (I2 66%).
Results
Better memory scores, mainly in older adults.
Effect sizes as reported
Overall SMD 0.29 (0.04 to 0.53); older adults 0.88 (0.22 to 1.55); younger 0.03 (-0.14 to 0.20).
Why this rating
Low because trials differ a lot, results come from older adults, and it is creatine alone.
Form and dose studied
Studied in many amounts across trials; see the studies table.
Who was studied
Healthy people, split into older and younger groups.
Limits
Single ingredient. Results do not transfer from older to young adults.
Why researchers looked
The brain uses a lot of energy, and creatine is part of how cells make it.
Traditional use
Brain formulas are modern products. Their single ingredients come from many sources: tea, coffee, Ayurvedic and Chinese herbs, mushrooms, and the diet.
Proposed mechanism Not established
Not established. The abstract says creatine plays a role in brain energy, and that supplements may raise brain creatine.
A proposed mechanism does not show that the effect happens in people.
Not covered in the abstract.
Lion's mane and apoaequorin
Not enough evidenceA 2025 review found few human trials of lion's mane, with memory-screening scores rising a little in two small studies. Apoaequorin was tested in one 90-day trial of 218 adults with memory concerns. Both are too thinly studied to judge.
2 studiesOne product in the apoaequorin trial. Lion's mane products varied.
Studies, doses and limits
What the trials found
The lion's mane review pooled one trial and one pilot study for a combined average rise of 1.17 points on a memory screening score, and lists possible stomach discomfort, headache and allergic reactions. The apoaequorin trial found better verbal learning and recall than placebo.
Results
Small and early. Single trials of single products.
Effect sizes as reported
MMSE combined mean +1.17 (lion's mane); apoaequorin gains not sized in the abstract.
Why this rating
Insufficient because there are very few human trials, and the lion's mane review also counts lab work.
Form and dose studied
One product in the apoaequorin trial. Lion's mane products varied.
Who was studied
Adults with and without dementia; adults aged 40 to 91 with memory concerns.
Limits
No repeat of the apoaequorin trial was read.
Why researchers looked
Both are sold in memory products and have lab and animal results.
Traditional use
Brain formulas are modern products. Their single ingredients come from many sources: tea, coffee, Ayurvedic and Chinese herbs, mushrooms, and the diet.
Proposed mechanism Not established
Not established in people. The apoaequorin trial abstract describes lab work on calcium handling in nerve cells.
A proposed mechanism does not show that the effect happens in people.
Lion's mane side effects were often unreported.
Preventing or slowing dementia: ginkgo, citicoline, vitamin E, omega-3 and B vitamins
Mixed findingsSeveral brain-formula ingredients were tested against dementia. A large trial found ginkgo did not lower dementia. A 2026 Cochrane review found ginkgo probably does little in mild cognitive impairment. NCCIH reports no convincing benefit from omega-3 or vitamin E for these aims. Citicoline looked better in poor-quality trials.
5 studiesGinkgo 120 mg twice a day in the large trial. Other amounts are in th…
Studies, doses and limits
What the trials found
In 3,069 adults aged 75 or older, a ginkgo extract did not lower the chance of dementia (HR 1.12) over about 6 years. The 2026 Cochrane review (82 trials, 10,613 people) found ginkgo probably has little to no effect in mild cognitive impairment (moderate certainty) and possibly small gains in dementia (low certainty, results varied widely). NCCIH (July 2022) states no conclusive evidence for ginkgo, no convincing efficacy of omega-3 supplements in mild-to-moderate Alzheimer disease, no evidence that vitamin E prevents mild impairment from progressing to dementia, and that B-vitamin trials of 6 to 24 months found no benefit while a longer meta-analysis suggests possible slowing. A 2023 review of seven low-quality citicoline studies found better scores in all seven. A 2026 review of 11 studies in mental disorders said evidence does not support citicoline or phosphatidylserine as cognitive enhancers.
Results
Mostly no benefit for ginkgo, omega-3 and vitamin E. Mixed for B vitamins. Citicoline positive but poor-quality.
Effect sizes as reported
Ginkgo dementia HR 1.12 (0.94 to 1.33); citicoline SMD 0.56 to 1.57 across analyses.
Why this rating
Mixed because ginkgo, omega-3 and vitamin E point to no benefit, B vitamins point both ways, and citicoline trials were poor quality.
Form and dose studied
Ginkgo 120 mg twice a day in the large trial. Other amounts are in the studies table.
Who was studied
Older adults, people with mild cognitive impairment, dementia, or mental disorders. Not healthy young adults.
Limits
These are people with memory disease or at older ages. They do not describe what a blend does in healthy adults.
Why researchers looked
Ginkgo, vitamin E, omega-3 and B vitamins are common in memory formulas and have been tried for dementia.
Traditional use
Brain formulas are modern products. Their single ingredients come from many sources: tea, coffee, Ayurvedic and Chinese herbs, mushrooms, and the diet.
Proposed mechanism Not established
Not established in the sources read.
A proposed mechanism does not show that the effect happens in people.
See the Safety tab for ginkgo and vitamin E bleeding cautions.
Multivitamins and memory in older adults
Low certaintyA large trial of 3,562 older adults found a daily multivitamin gave a small gain in one memory test after 1 year and 3 years, but not in other tests. Pooled COSMOS trials found small gains in overall thinking and memory. This is a multivitamin, not a brain formula.
3 studiesOne multivitamin product in COSMOS-Web.
Studies, doses and limits
What the trials found
COSMOS-Web (3,562 adults) found better immediate recall at 1 year (p = 0.025) with no change in other tests. A pooled analysis of three COSMOS studies (about 5,200 people) found small gains in global cognition (0.07 SD units) and episodic memory (0.06). NCCIH says taking a multivitamin or high amounts of single vitamins has no clear benefit for thinking in well-nourished people.
Results
Small gains in memory in older adults in one trial program. NCCIH is less positive for well-nourished people.
Effect sizes as reported
Global cognition 0.07 SD units (0.03 to 0.11); episodic memory 0.06 (0.03 to 0.10).
Why this rating
Low because gains are small, come from one trial program, and NCCIH reads the broader evidence as showing no clear benefit.
Form and dose studied
One multivitamin product in COSMOS-Web.
Who was studied
Adults 60 and older.
Limits
Not a test of brain formulas. Older adults only.
Why researchers looked
Many brain formulas include vitamins, and a multivitamin is the best-tested vitamin mix.
Traditional use
Brain formulas are modern products. Their single ingredients come from many sources: tea, coffee, Ayurvedic and Chinese herbs, mushrooms, and the diet.
Proposed mechanism Not established
Not established. The trials did not measure whether low vitamin levels explained the result.
A proposed mechanism does not show that the effect happens in people.
Not covered in the abstracts.
Do blends beat their single ingredients?
Not enough evidenceNo study read showed that a finished blend beats its separate ingredients. Reviews rate the usual ingredients one by one and say the evidence is mostly low. Adding up single-ingredient results to judge a blend is not supported.
2 studiesNot applicable.
Studies, doses and limits
What the trials found
A 2021 review of nine ingredients (69 publications) in healthy adults found low-certainty, inconsistent evidence and said not always knowing what is in a product makes weighing risks hard. A 2023 review of 103 memory products listed ingredients with no compelling evidence, some evidence, or mixed results, and found every product had at least one of 18 common ingredients.
Results
No evidence that mixing adds value.
Why this rating
Insufficient because no head-to-head trial of a blend and its parts was found.
Who was studied
Healthy adults in the 2021 review.
Limits
Both reviews cover single ingredients and market surveys, not finished-blend trials.
Why researchers looked
A longer ingredient list sounds stronger, so researchers have been asked whether it is.
Traditional use
Brain formulas are modern products. Their single ingredients come from many sources: tea, coffee, Ayurvedic and Chinese herbs, mushrooms, and the diet.
Proposed mechanism Not established
Not established.
A proposed mechanism does not show that the effect happens in people.
See the Safety tab.
Connections to the rest of health
How Multi-Ingredient Brain Formulas connects to the rest of our health knowledge graph. Every link says what kind of connection it is. A safety link (for example to the liver) is a warning, not a benefit. A study that merely mentions a topic never creates a benefit link.
Explore every connection: goals, body systems, organs, symptoms, genes
A. Wellness goals
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Better Focus | Very low certainty | Trials of finished brain blends: Only a few small trials have tested a finished brain blend. Two tested a single serving and one tested ten herbs for 90 days. Some tests got faster, but one trial saw worse memory scores, and the maker paid for it. These trials cannot say which ingredient did the work or whether any blend beats its single ingredients. | 24 13 1 | |
| Cognitive Performance | Very low certainty | Trials of finished brain blends: Only a few small trials have tested a finished brain blend. Two tested a single serving and one tested ten herbs for 90 days. Some tests got faster, but one trial saw worse memory scores, and the maker paid for it. These trials cannot say which ingredient did the work or whether any blend beats its single ingredients. | 24 13 1 | |
| Memory Support | Very low certainty | Trials of finished brain blends: Only a few small trials have tested a finished brain blend. Two tested a single serving and one tested ten herbs for 90 days. Some tests got faster, but one trial saw worse memory scores, and the maker paid for it. These trials cannot say which ingredient did the work or whether any blend beats its single ingredients. | 24 13 1 | |
| Better Focus | Low certainty | Short-term attention from caffeine and L-theanine: Caffeine and L-theanine are the ingredients with the most steady short-term attention results. A pooled review found a single serving of L-theanine speeded choice reaction time. Caffeine plus L-theanine showed small gains in the first two hours, with wide uncertainty. These trials tested the ingredients alone, not finished blends. | 12 7 16 19 | |
| Cognitive Performance | Low certainty | Short-term attention from caffeine and L-theanine: Caffeine and L-theanine are the ingredients with the most steady short-term attention results. A pooled review found a single serving of L-theanine speeded choice reaction time. Caffeine plus L-theanine showed small gains in the first two hours, with wide uncertainty. These trials tested the ingredients alone, not finished blends. Memory from bacopa, ashwagandha and other herbs: Reviews of single herb extracts found small gains. Bacopa taken for at least 12 weeks shortened some reaction times and improved free recall on some tests. A 2026 review of 20 trials found ashwagandha improved memory, attention and executive function. Rhodiola results are mixed and not separated in the review. These tested single extracts, not blends. | 12 7 16 19 9 17 26 31 5 8 | |
| Memory Support | Low certainty | Memory from bacopa, ashwagandha and other herbs: Reviews of single herb extracts found small gains. Bacopa taken for at least 12 weeks shortened some reaction times and improved free recall on some tests. A 2026 review of 20 trials found ashwagandha improved memory, attention and executive function. Rhodiola results are mixed and not separated in the review. These tested single extracts, not blends. Memory from creatine: A 2023 pooled review of eight trials found creatine improved memory test scores overall, with a clear gain in older adults (66 to 76) and none in younger people. Creatine appears in some brain formulas. | 9 17 26 31 20 14 15 5 8 | |
| Brain Health | Mixed findings | Preventing or slowing dementia: ginkgo, citicoline, vitamin E, omega-3 and B vitamins: Several brain-formula ingredients were tested against dementia. A large trial found ginkgo did not lower dementia. A 2026 Cochrane review found ginkgo probably does little in mild cognitive impairment. NCCIH reports no convincing benefit from omega-3 or vitamin E for these aims. Citicoline looked better in poor-quality trials. | 6 23 2 10 30 | |
| Memory Support | Low certainty | Multivitamins and memory in older adults: A large trial of 3,562 older adults found a daily multivitamin gave a small gain in one memory test after 1 year and 3 years, but not in other tests. Pooled COSMOS trials found small gains in overall thinking and memory. This is a multivitamin, not a brain formula. | 25 22 30 | |
| Brain Health | Low certainty | Multivitamins and memory in older adults: A large trial of 3,562 older adults found a daily multivitamin gave a small gain in one memory test after 1 year and 3 years, but not in other tests. Pooled COSMOS trials found small gains in overall thinking and memory. This is a multivitamin, not a brain formula. | 25 22 30 |
B. Body systems
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Brain | Biological association | Very low certainty | Studied for: Trials of finished brain blends Studied for: Short-term attention from caffeine and L-theanine | 24 13 1 12 7 16 19 9 17 26 31 20 14 15 6 23 2 10 30 25 22 5 8 |
| Nervous System | Biological association | Very low certainty | Studied for: Trials of finished brain blends Studied for: Short-term attention from caffeine and L-theanine | 24 13 1 12 7 16 19 9 17 26 31 20 14 15 6 23 2 10 30 25 22 5 8 |
I. Biomarkers
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Choice reaction time | Biological association | Low certainty | Measured in trials: shorter times with L-theanine; mixed with caffeine plus theanine. A lab change is not the same as a health benefit. | 7 19 |
| Task speed and working memory on computer tests | Biological association | Very low certainty | Measured in trials: faster in two single-serving trials; slower memory in the 90-day trial. A lab change is not the same as a health benefit. | 1 13 24 |
| New dementia | Biological association | Moderate certainty | Measured in trials: no reduction with ginkgo. A lab change is not the same as a health benefit. | 6 |
| Memory test scores | Biological association | Low certainty | Measured in trials: higher scores in several reviews. A lab change is not the same as a health benefit. | 26 20 25 |
L. Active compounds
| Connected to | Kind of connection | Evidence status | Context | Studies |
|---|---|---|---|---|
| Caffeine | Biological association | Human | The most steady short-term attention result of the usual ingredients; most often named in a survey of active adults (21.7%). | 12 18 |
| L-theanine | Biological association | Human | Single servings shortened choice reaction time in a 31-trial review. | 7 16 19 |
| Bacopa (Bacopa monnieri) extract | Biological association | Human | Faster reaction times and some free-recall gains in trials of 12 weeks or more. | 9 17 |
| Ashwagandha and rhodiola extracts | Biological association | Human | Memory, attention and executive-function gains reported for ashwagandha. | 26 31 |
| Ginkgo (Ginkgo biloba) extract | Biological association | Human | No lower dementia rate in a large trial; bleeding concern. | 6 23 |
| Citicoline, alpha-GPC and phosphatidylserine | Biological association | Human | Citicoline: positive but poor-quality trials. Alpha-GPC: stroke association. Phosphatidylserine: not supported in mental disorders. | 2 11 10 |
| Creatine | Biological association | Human | Better memory scores in older adults in a pooled review. | 20 |
| Lion's mane (Hericium erinaceus) | Biological association | Human and lab | A few small human trials; many lab results. | 14 |
| Apoaequorin | Biological association | Human | One 90-day trial in adults with memory concerns. | 15 |
| B vitamins, vitamin E, omega-3 | Biological association | Human (reviews) | NCCIH: no convincing benefit for dementia aims, with mixed B-vitamin results. | 30 |
Each connection is stored with the ingredient, the connected record, the kind of connection, the evidence status, the supporting studies, the preparation or compound involved, and a review date (last reviewed October 26, 2026).
Evidence at a glance: what the research found for 8 outcomes
Each outcome below is one thing researchers measured. Certainty is how far the evidence can be trusted, not how well it works. The full studies are on the next tab.
The evidence
The research centre for Multi-Ingredient Brain Formulas. Every record here was checked against PubMed or the publisher's page; we never list a study we have not verified.
Evidence by outcome
Bars show how many studies we found for each outcome, not how well it works. People are added up across trials only (reviews are not added, to avoid double counting).
How we rate evidence
High certainty
Several well-run trials or reviews agree; further research is unlikely to change the picture much.
Moderate certainty
Good trials point the same way, but some doubt remains.
Low certainty
Small, short or inconsistent trials. The finding could change with better research.
Very low certainty
Very little or very weak human data. Treat as a possibility only.
Mixed findings
Trials or reviews disagree with each other.
Not enough evidence
Not enough human research to say either way.
Evidence against
Good research found no benefit, or found harm.
We take the reviewers' own risk-of-bias and GRADE statements where they exist, and otherwise judge from study size, design, consistency, directness and whether a product matches what is sold. Many publications do not make evidence high. Method note: We started from our existing table of brain-formula ingredients, re-read PubMed abstracts for every review, trial and lab study cited, and read the NCCIH and FDA pages in full. Only abstracts were read for studies. The NIH Office of Dietary Supplements page was blocked and is marked unread.
Study library: every study we checked 31
| Study | Design | People | Product, dose, length | Result |
|---|---|---|---|---|
| Best 2021 Acute effects of combined Bacopa, American ginseng and whole coffee fruit on working memory and cerebral haemodynamic response of the prefrontal cortex: a double-blind, placebo-controlled study. Nutr Neurosci · PMID 31736428 · DOI |
Randomised controlled trial |
40 40 healthy adults aged 18 to 60 |
Bacopa, American ginseng and whole coffee fruit extract in one supplement Finished product (extracts) Not given in the abstract One serving; tests 45 minutes later · vs Placebo |
After the active product, accuracy (p < 0.01) and response time (p < 0.05) on a working-memory task were better than placebo, with less front-brain activation. p < 0.01 accuracy; p < 0.05 response time (Not given in the abstract) Methods, limits and fundingOutcomes: Working-memory (N-back) accuracy and speed, brain blood-flow signal in the front of the brain (fNIRS) Limitations: 40 people, one serving. The coffee-fruit extract contains caffeine-like compounds; the abstract does not separate their share. Not a test of daily use. Funding and conflicts: No conflict declared in the record read. Read: abstract |
| Bonvicini 2023 Is Citicoline Effective in Preventing and Slowing Down Dementia?-A Systematic Review and a Meta-Analysis. Nutrients · PMID 36678257 · DOI |
Systematic review meta analysis |
7 studies (6 pooled) in people with mild cognitive impairment, Alzheimer disease or post-stroke dementia | Citicoline Oral or injected citicoline (as in the studies) Not given in the abstract Varied · vs Varied |
All seven studies reported better thinking scores, and the pooled result was positive. The authors say study quality was poor and bias favoured citicoline. Pooled SMD from 0.56 to 1.57 across analyses (0.37 to 0.75; 0.77 to 2.37) Methods, limits and fundingOutcomes: Cognitive status scores Limitations: Poor quality. Patients with disease, not healthy people. Funding and conflicts: The authors declare no conflict. Read: abstract |
| Crawford 2020 A Public Health Issue: Dietary Supplements Promoted for Brain Health and Cognitive Performance. J Altern Complement Med · PMID 32119795 · DOI |
Laboratory analysis product |
12 12 brain-health supplement products picked from 650 on the market, chosen because US service members asked about them |
Brain-health dietary supplement products Finished products · vs Label compared with lab analysis |
Eight of 12 products (67%) had at least one label ingredient that the lab did not detect. Ten of 12 (83%) held compounds that were not on the label. The authors say some products should be seen as adulterated and misbranded. 8 of 12 and 10 of 12 (Not applicable) Methods, limits and fundingOutcomes: Whether label ingredients were found, and whether unlabelled compounds were present Limitations: Only 12 products, picked by interest, not a random sample of the market. Funding and conflicts: No competing financial interests declared. Read: abstract |
| Crawford 2020 The scoop on brain health dietary supplement products containing huperzine A. Clin Toxicol (Phila) · PMID 31990212 · DOI |
Laboratory analysis product |
22 22 supplements listing huperzine A, chosen because service members asked about them |
Products listing huperzine A Finished products · vs Label compared with lab analysis |
16 of 22 (73%) had at least one label ingredient not detected and 16 (73%) held unlabelled compounds. 9 (41%) listed ingredients that do not meet FDA rules for supplement ingredients. Stimulants found included higenamine, vinpocetine, noopept and hordenine. Only 2 had huperzine A within 10% of the label. 16 of 22; 16 of 22; 9 of 22; 2 of 22 (Not applicable) Methods, limits and fundingOutcomes: Presence of label ingredients, unlabelled compounds, and huperzine A amount Limitations: Products picked by interest, not a random sample. Huperzine A products only. Funding and conflicts: No conflict declared. Read: abstract |
| Crawford 2021 Dietary Supplement Ingredients for Optimizing Cognitive Performance Among Healthy Adults: A Systematic Review. J Altern Complement Med · PMID 34370563 · DOI |
Systematic review |
69 publications on nine ingredients with at least three studies each, in healthy adults | Bacopa, choline, creatine, omega-3, ginkgo, ginseng, rhodiola, tyrosine, valerian Supplements Various Various · vs Placebo |
Of 54 ingredients found, only nine had enough studies. Overall certainty was low, studies were inconsistent and imprecise, and many were flawed. The authors say not knowing what is in a product also makes weighing risks hard. Numbers not given in the abstract (Not given in the abstract) Methods, limits and fundingOutcomes: Cognitive performance in healthy adults Limitations: Reviews single ingredients only. Funding and conflicts: No conflict statement in the record read. Read: abstract |
| DeKosky 2008 Ginkgo biloba for prevention of dementia: a randomized controlled trial. JAMA · PMID 19017911 · DOI |
Randomised controlled trial |
3069 3,069 adults aged 75 or older, with normal thinking (2,587) or mild impairment (482) |
Ginkgo biloba extract Extract 120 mg twice a day Median follow-up 6.1 years · vs Placebo |
Ginkgo did not lower the chance of dementia or Alzheimer disease. Side effects were similar to placebo. Dementia HR 1.12; Alzheimer HR 1.16; progression from mild impairment HR 1.13 (0.94 to 1.33; 0.97 to 1.39; 0.85 to 1.50) Methods, limits and fundingOutcomes: New dementia and Alzheimer disease Limitations: One extract in older adults. Does not cover other ginkgo products or younger people. Funding and conflicts: Public funding (US National Institutes of Health); no conflict reported. Read: abstract |
| Gerolymos 2026 Cognitive and affective effects of L-Theanine: a systematic review and meta-analysis of 31 randomized trials. Mol Psychiatry · PMID 42410082 · DOI |
Systematic review meta analysis |
1168 31 randomised trials in healthy and clinical groups |
L-theanine (an amino acid from tea) Oral supplement Single dose of 200 mg in the reaction-time result (as stated in the abstract) Single doses and repeated doses · vs Placebo |
A single 200 mg amount 30 to 60 minutes before testing improved choice reaction time. The stress result was modest and driven by studies at high risk of bias. No serious adverse events were reported. Choice reaction time SMD 0.51; acute stress SMD 0.31 (Choice reaction time 0.25 to 0.77) Methods, limits and fundingOutcomes: Choice reaction time, stress, mood, fatigue, dropouts Limitations: Single ingredient, not a blend. Short-term lab tasks. Stress result relied on weaker studies. Funding and conflicts: One author founded a company that sells dietary supplements; the others report no conflicts. Read: abstract |
| Hersant 2023 Over the Counter Supplements for Memory: A Review of Available Evidence. CNS Drugs · PMID 37603263 · DOI |
Narrative review and market survey |
103 memory supplements sold in US pharmacies and grocery stores; their 18 most common ingredients | Memory supplement ingredients Supplements Not given in the abstract Varied · vs Varied |
The authors list ingredients with no compelling evidence (including apoaequorin, coenzyme Q10, coffee extracts, L-theanine, omega-3 and vitamins B6, B9 and B12), some evidence (including ashwagandha, choline, curcumin, ginger, lion's mane, polyphenols and phosphatidylserine) and mixed evidence (including carnitine, ginkgo, huperzine A, vitamin D and vitamin E). Every product held at least one of the 18 ingredients. Not applicable (Not applicable) Methods, limits and fundingOutcomes: Evidence for memory benefit by ingredient Limitations: Narrative review; ratings are the authors' own. Funding and conflicts: No conflict statement in the record read. Read: abstract |
| Kongkeaw 2014 Meta-analysis of randomized controlled trials on cognitive effects of Bacopa monnieri extract. J Ethnopharmacol · PMID 24252493 · DOI |
Systematic review meta analysis |
518 9 randomised trials, 518 people; 437 in the pooled result |
Standardized bacopa extract Extract Not given in the abstract At least 12 weeks · vs Placebo |
Pooled results showed a shorter Trail B time and a shorter choice reaction time. The authors say only a large head-to-head trial could give a firm answer. Trail B -17.9; choice reaction time -10.6 (units printed as ms in the abstract) (-24.6 to -11.2; -12.1 to -9.2) Methods, limits and fundingOutcomes: Trail B test time and choice reaction time Limitations: Standardized extracts taken for at least 12 weeks, not blends. Review is from 2014. Funding and conflicts: No conflict statement in the record read. Read: abstract |
| Kucuksahin 2026 The Impact of Citicoline/Phosphatidylserine Supplementation on Cognitive Performance and Executive Functions in Mental Disorders: A Systematic Review of Controlled Trials. Hum Psychopharmacol · PMID 42538853 · DOI |
Systematic review |
11 studies (10 randomised) in children and adults with ADHD, mood disorders, substance use disorders and schizophrenia | Citicoline and phosphatidylserine Oral supplements Not given in the abstract Varied · vs Placebo or usual care |
Results were mixed. In ADHD, three of five studies reported better attention or impulsivity and two found no difference. The authors conclude the evidence does not support these as cognitive enhancers in mental disorders. Numbers not given in the abstract (Not given in the abstract) Methods, limits and fundingOutcomes: Attention, impulsivity, memory and executive function Limitations: High risk of bias; mixed diagnoses. Funding and conflicts: The authors declare no conflicts. Read: abstract |
| Lee 2021 Association of L-α Glycerylphosphorylcholine With Subsequent Stroke Risk After 10 Years. JAMA Netw Open · PMID 34817582 · DOI |
Retrospective cohort study |
12008977 12 million South Korean adults aged 50 or older; 108,877 used alpha-GPC |
Alpha-GPC (L-alpha glycerylphosphorylcholine), prescribed in Korea Prescription use recorded in insurance data Dose-response by months of prescription 10-year follow-up · vs Matched non-users |
Users had a higher risk of stroke than non-users, rising with longer use. This is an association; the authors say mechanisms need study. Total stroke aHR 1.43 after matching (1.41 to 1.46) Methods, limits and fundingOutcomes: New stroke Limitations: Observational. Users were older and may differ in ways not measured. Korean prescription use, not supplement shop products. Funding and conflicts: No conflicts reported. Read: abstract |
| Lorca 2023 Plant-derived nootropics and human cognition: A systematic review. Crit Rev Food Sci Nutr · PMID 34978226 · DOI |
Systematic review |
256 papers on humans, 2000 to 2021, healthy people and people with disease | Plant-derived nootropics (ginkgo, bacopa, ashwagandha, caffeine and others) Mixed Not given in the abstract Varied · vs Varied |
The authors say ginkgo was most relevant for perception and movement, bacopa for language, learning and memory, ashwagandha for anxiety and social cognition, and caffeine for attention and executive function. They also point to inconsistencies between studies. Numbers not given in the abstract (Not given in the abstract) Methods, limits and fundingOutcomes: Six brain domains: perception and movement, language, learning and memory, attention, executive function, social cognition Limitations: A broad review with no pooled numbers in the abstract and no certainty rating per ingredient. These are single plants, not finished blends. Funding and conflicts: No conflict statement in the record read. Read: abstract |
| Medrano 2022 Acute Effect of a Dietary Multi-Ingredient Nootropic as a Cognitive Enhancer in Young Healthy Adults: A Randomized, Triple-Blinded, Placebo-Controlled, Crossover Trial. Front Nutr · PMID 35634417 · DOI |
Randomised crossover trial |
26 26 healthy adults, average age about 25, half women |
A sports-nutrition powder sold for gamers (multi-ingredient) Powder mixed in a drink (ingredient list not in the abstract) 10 g, one serving Single serving; tests 30 minutes later · vs Placebo (maltodextrin) |
Faster response times and better accuracy on several tests than placebo, including processing speed, impulse control, spatial working memory and mental flexibility. No difference in verbal fluency, motivation or anxiety. Heart rate and heart-rate variability were similar. Effect sizes about 0.4 to 0.6 (Not given in the abstract) Methods, limits and fundingOutcomes: Reaction time and accuracy on thinking tests, mood, heart rate Limitations: Only 26 people and one serving. Tests were taken 30 minutes later, so it says nothing about daily use. The ingredient list was not in the abstract, so which ingredient did the work (for example caffeine) cannot be told. Funding and conflicts: No commercial relationships declared by the authors. The product is made by a sports-nutrition company. Read: abstract |
| Menon 2025 Benefits, side effects, and uses of Hericium erinaceus as a supplement: a systematic review. Front Nutr · PMID 40959699 · DOI |
Systematic review |
5 randomised trials, 3 pilot trials, 15 lab studies and other reports | Lion's mane (Hericium erinaceus) mushroom products Fruiting body and mycelium products Not given in the abstract Varied · vs Varied |
In one trial and one pilot trial, memory-screening scores rose by a combined average of 1.17 points. The review lists possible side effects of stomach discomfort, headache and allergic reactions, often unreported. Lab results were in cells and animals. MMSE combined weighted mean +1.17 (Not given in the abstract) Methods, limits and fundingOutcomes: Cognitive scores (MMSE), mood, gut markers, side effects Limitations: Very few human trials. Many of the claims in the abstract come from lab work. Funding and conflicts: No commercial conflicts declared. Read: abstract |
| Moran 2016 Effects of a Supplement Containing Apoaequorin on Verbal Learning in Older Adults in the Community. Adv Mind Body Med · PMID 26878676 |
Randomised controlled trial |
218 218 adults aged 40 to 91 with memory concerns |
Apoaequorin (a protein originally found in jellyfish) in a supplement Capsule product Not given in the abstract 90 days · vs Matched placebo |
The apoaequorin group improved on the verbal learning and delayed recall tests during the 90 days compared with placebo. The product was well tolerated. Statistically significant, size not given in the abstract (Not given in the abstract) Methods, limits and fundingOutcomes: Computer tests of verbal learning and delayed recall Limitations: One trial of one product. Funding not stated in the record. Funding and conflicts: No conflict statement in the record read. Read: abstract |
| Mátyus 2025 Promising, but Not Completely Conclusive-The Effect of l-Theanine on Cognitive Performance Based on the Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Clinical Trials. J Clin Med · PMID 41227106 · DOI |
Systematic review meta analysis |
148 5 randomised trials in healthy adults |
L-theanine Oral supplement Not given in the abstract Varied · vs Placebo |
Better on one fast-attention measure (a 15 ms shorter recognition reaction time) but no clear effect on simple reaction time or the Stroop test. The authors call the result promising but not conclusive. Mean difference -15.20 ms on the attention measure (-28.99 to -1.41 ms) Methods, limits and fundingOutcomes: Rapid visual information processing, simple and recognition reaction time, Stroop test Limitations: Only five small trials with different products. Funding and conflicts: The authors declare no conflicts; public research funding listed. Read: abstract |
| Pase 2012 The cognitive-enhancing effects of Bacopa monnieri: a systematic review of randomized, controlled human clinical trials. J Altern Complement Med · PMID 22747190 · DOI |
Systematic review |
6 randomised trials in adults without dementia | Three different bacopa extracts Extract 300 to 450 mg of extract a day, as stated in the abstract 12 weeks · vs Placebo |
Memory free recall improved on 9 of 17 tests. There was little sign of benefit in other thinking skills. 9 of 17 free-recall tests improved (Not given in the abstract) Methods, limits and fundingOutcomes: Memory and other thinking tests Limitations: Small number of trials; mixed tests. Funding and conflicts: No conflict statement in the record read. Read: abstract |
| Pastina 2026 Nootropic Supplements and Exercise: Patterns and Perceptions of Cognitive Enhancer Use in Physically Active Individuals. J Diet Suppl · PMID 41269033 · DOI |
Survey |
152 152 physically active adults (average age about 27) in an online survey |
Nootropic supplements (36 reported) Various |
Caffeine (21.7%), creatine (9.8%), DHA (7.0%), L-theanine and nicotine (6.6% each) and ashwagandha (6.1%) were most often named. The most common reason was to raise energy and motivation (34.8%). Not applicable (Not applicable) Methods, limits and fundingOutcomes: Which nootropics, how often, why, and how effective they felt Limitations: Small online sample; self-reported effects. Funding and conflicts: No conflict declared. Read: abstract |
| Payne 2025 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. Nutr Rev · PMID 40314930 · DOI |
Systematic review meta analysis |
50 randomised trials in healthy people (15 pooled) | Tea, L-theanine, and L-theanine plus caffeine Oral Not given in the abstract Single servings, tested in the first and second hour · vs Placebo |
Theanine plus caffeine gave small-to-moderate differences from placebo in the first two hours on some tests, such as attention-switching accuracy. Theanine alone shortened choice reaction time in the first hour. The authors say the confidence intervals often showed real uncertainty. Attention switching accuracy (hour 2) SMD 0.33; digit vigilance accuracy (hour 2) 0.20; choice reaction time (hour 1) -0.48 for the pair, -0.35 for theanine alone (0.13 to 0.54; 0.02 to 0.38; -1.01 to 0.05; -0.61 to -0.10) Methods, limits and fundingOutcomes: Reaction time, accuracy on attention tasks, mood, sleep Limitations: Effects last about two hours. Several intervals cross zero. Funding and conflicts: Funded by a tea company; two authors work for tea or consumer-goods companies. Read: abstract |
| Prokopidis 2023 Effects of creatine supplementation on memory in healthy individuals: a systematic review and meta-analysis of randomized controlled trials. Nutr Rev · PMID 35984306 · DOI |
Systematic review meta analysis |
10 trials, 8 pooled, in healthy people | Creatine supplements Oral supplement About 2.2 to 20 g a day across trials (as stated) 5 days to 24 weeks · vs Placebo |
Overall, memory scores were better than placebo. Older adults (66 to 76) gained clearly; younger people (11 to 31) did not. Overall SMD 0.29; older adults 0.88; younger people 0.03 (0.04 to 0.53; 0.22 to 1.55; -0.14 to 0.20) Methods, limits and fundingOutcomes: Memory test scores Limitations: Large differences between trials (I2 66%). Result is for older adults, not young adults. Funding and conflicts: No conflict statement in the record read. Read: abstract |
| Upmanis 2024 Purchasing "Nootropics" Online: Identification and Quantification of Ingredients in Phenibut-Containing Products. Medicina (Kaunas) · PMID 39459348 · DOI |
Laboratory analysis product |
6 6 phenibut-containing products bought from three online sellers |
Phenibut-containing "nootropic" capsules Finished products · vs Label compared with lab analysis |
Three products had much less phenibut than claimed and one had much more. All carried declared and undeclared ingredients. Phenibut is a prescription drug in some countries and has case reports of toxicity and withdrawal. 3 of 6 much lower; 1 of 6 much higher (Not applicable) Methods, limits and fundingOutcomes: Phenibut content and other ingredients Limitations: Six products only. Funding and conflicts: One author works for a company that makes a prescription phenibut medicine. Read: abstract |
| Vyas 2024 Effect of multivitamin-mineral supplementation versus placebo on cognitive function: results from the clinic subcohort of the COcoa Supplement and Multivitamin Outcomes Study (COSMOS) randomized clinical trial and meta-analysis of 3 cognitive studies within COSMOS. Am J Clin Nutr · PMID 38244989 · DOI |
Randomised controlled trial and meta analysis |
5203 573 older adults in a clinic study, plus 2,158 and 2,472 in two other COSMOS studies |
A daily multivitamin-multimineral Tablet Not given in the abstract 2 years in the clinic study · vs Placebo |
In the clinic study, global thinking showed a small, borderline gain and episodic memory a small gain. Pooling the three COSMOS studies showed small gains in both. Pooled global cognition 0.07 SD units; episodic memory 0.06 (0.03 to 0.11; 0.03 to 0.10) Methods, limits and fundingOutcomes: Global thinking score and episodic memory Limitations: Gains are small. The authors link the global result to about two years less cognitive ageing. Funding and conflicts: Public funding (US National Institutes of Health). Read: abstract |
| Wieland 2026 Ginkgo biloba for cognitive impairment and dementia. Cochrane Database Syst Rev · PMID 41641880 · DOI |
Systematic review meta analysis |
10613 82 trials with 10,613 people with memory complaints, mild cognitive impairment or dementia |
Ginkgo biloba Extract Not given in the abstract Often 6 months · vs Placebo, usual care or other treatment |
In mild cognitive impairment, moderate-certainty evidence says ginkgo probably has little or no effect. In dementia, low-certainty evidence suggests possible small gains, with large differences between trials. Serious side effects were not more common (high certainty in mild impairment). Mild impairment, global status MD -0.03; serious side effects RR 0.95 (-0.06 to 0.01; 0.82 to 1.09) Methods, limits and fundingOutcomes: Overall status, thinking tests, daily activities, side effects Limitations: Dementia results varied widely (I2 up to 96%). Only four of the studies had low risk of bias throughout. Funding and conflicts: Cochrane review. Some authors work for Cochrane groups; none had product ties listed. Read: abstract |
| Wightman 2023 Chronic supplementation of a multi-ingredient herbal supplement increases speed of cognitive task performance alongside changes in the urinary metabolism of dopamine and the gut microbiome in cognitively intact older adults experiencing subjective memory decline: a randomized, placebo controlled, parallel groups investigation. Front Nutr · PMID 37885445 · DOI |
Randomised controlled trial |
128 128 adults aged 55 to 75 with self-noticed memory decline |
A herbal supplement with ten herbs including bacopa, gotu kola, turmeric, reishi, rosemary, holy basil and green tea Mixed herb powders and extracts (finished product) Not given in the abstract 90 days · vs Placebo |
The authors report faster task speed and fewer false alarms on one attention test. They also saw worse memory scores on the herb product, and say unequal group make-up before and after COVID-19 makes that hard to read. Not given in the abstract (Not given in the abstract) Methods, limits and fundingOutcomes: Computer tests of memory, attention and speed; urine and stool markers Limitations: One product, one trial. Groups were unevenly made up. Memory got worse in the herb group, which the authors could not explain. The maker helped prepare the paper. Funding and conflicts: Funded by the herb company that makes the product; one author works for it. The funder helped prepare the manuscript. Read: abstract |
| Yeung 2023 Multivitamin Supplementation Improves Memory in Older Adults: A Randomized Clinical Trial. Am J Clin Nutr · PMID 37244291 · DOI |
Randomised controlled trial |
3562 3,562 older adults in the COSMOS-Web study |
A daily multivitamin-multimineral Tablet (a widely sold senior multivitamin) Not given in the abstract 3 years · vs Placebo |
Immediate recall was better with the multivitamin at 1 year (primary result) and across the three years. Other thinking tests did not differ. The authors put the gain at about 3.1 years of age-related memory change. Primary result t = 2.25, p = 0.025 (Not given in the abstract) Methods, limits and fundingOutcomes: Memory recall (ModRey test) at 1 year; other thinking tests Limitations: Internet-based tests. A multivitamin, not a brain formula. Memory gain was small and other tests did not change. Funding and conflicts: Public funding (US National Institutes of Health). Supply of the product by a company is not stated in the abstract. Read: abstract |
| Zhu 2026 Effects of Withania somnifera (L.) Dunal (Ashwagandha) on cognitive and physical function in adults: a systematic review and meta-analysis. Front Pharmacol · PMID 42199854 · DOI |
Systematic review meta analysis |
1249 20 randomised trials in adults |
Ashwagandha (Withania somnifera) extracts Root or root and leaf extracts Not given in the abstract Varied · vs Placebo |
Better scores for memory, attention and processing speed, and executive function than placebo. Most studies were rated high or moderate quality by the authors. Memory SMD 0.52; attention and processing speed 0.29; executive function -0.42 (lower is better on those tests) (0.27 to 0.78; 0.07 to 0.51; -0.70 to -0.13) Methods, limits and fundingOutcomes: Memory, attention, executive function, muscle strength, testosterone, body weight Limitations: Different extracts and tests were pooled. Not a test of blends. Only abstract read. Funding and conflicts: No commercial conflicts declared. Read: abstract |
| s-fda-101 FDA: FDA 101: Dietary Supplements (page dated 06/02/2022) · Source |
Regulator page n/a |
Methods, limits and fundingRead: full page text | ||
| s-fda-caffeine FDA: Spilling the Beans: How Much Caffeine is Too Much? (page dated 08/28/2024) · Source |
Regulator page n/a |
Methods, limits and fundingRead: full page text | ||
| s-fda-label FDA: Dietary Supplement Labeling Guide, Chapter IV: Nutrition Labeling (page dated 04/01/2005) · Source |
Regulator page n/a |
Methods, limits and fundingRead: full page text | ||
| s-nccih NCCIH: Dietary Supplements and Cognitive Function, Dementia, and Alzheimer's Disease: What the Science Says (July 2022) · Source |
Regulator page n/a |
Methods, limits and fundingRead: full page text | ||
| Łuszczak 2026 Clinical evidence for the adaptogenic effects of Withania somnifera and Rhodiola rosea - A systematic review with molecular interpretation of psychometric outcomes. Ann Agric Environ Med · PMID 41906501 · DOI |
Systematic review |
24 randomised trials: 19 on ashwagandha and 5 on rhodiola, 10 to 590 people each | Ashwagandha and rhodiola standardized extracts Extract Ashwagandha 120 to 1,000 mg a day; rhodiola 290 to 1,500 mg a day (as stated) 3 to 16 weeks · vs Placebo |
Benefits reported for stress, mood, sleep and some thinking tasks, with the five rhodiola trials not separated for cognition in the abstract. The authors note differences between studies, short durations and small samples. Numbers not given in the abstract (Not given in the abstract) Methods, limits and fundingOutcomes: Stress, anxiety, sleep, cognition, muscle strength Limitations: The abstract does not split thinking results by herb. Funding and conflicts: No conflict statement in the record read. Read: abstract |
What we do not know yet
- No trial compared a finished blend with its separate ingredients.
- No independent repeat of any blend trial was read.
- Long-term safety of daily blend use was not found.
- No interaction studies with medicines for blends were found.
- Heavy-metal testing of brain formulas was not found.
- NIH Office of Dietary Supplements pages could not be read.
- Ingredient lists and amounts of the tested blends were not in the abstracts.
How new research is added
New studies are found by a saved PubMed search and placed in a review queue before the page changes.
Lab markers
What changed in blood or saliva tests during trials. A changed number is not the same as feeling or being healthier, and we give no "normal ranges".
Other 4
Choice reaction time
Shorter times with L-theanine; mixed with caffeine plus theanine in trials
How quickly a person presses the right key when one of several signals appears. A shorter time means faster responses.
Low certaintyResults and what it means
Why it was measured
A common way to measure attention and speed in short trials.
Statistical vs. clinical meaning
Changes are small and short-lived.
Safety implication
No safety problem in the abstracts read.
Task speed and working memory on computer tests
Faster in two single-serving trials; slower memory in the 90-day trial in trials
Computer tasks that score how fast and how accurately people respond or hold information in mind for a moment.
Very low certaintyResults and what it means
Why it was measured
Used in the finished-blend trials.
Statistical vs. clinical meaning
Different products and tests; no repeat of any trial.
Safety implication
Not reported in the abstracts.
| Study | Result | People | Product |
|---|---|---|---|
| 1 | Working-memory accuracy (p < 0.01) and response time (p < 0.05) better 45 minutes after the supplement | 40 healthy adults | Bacopa, ginseng and coffee fruit extract |
| 13 | Faster responses and better accuracy on several tests 30 minutes after one serving; no difference in verbal fluency | 26 young adults | Multi-ingredient powder |
| 24 | Faster task speed after 90 days, but worse memory scores | 128 adults aged 55 to 75 | Ten-herb product |
New dementia
No reduction with ginkgo in trials
Whether a person is diagnosed with dementia during follow-up. This is a clinical outcome, not a blood marker.
Moderate certaintyResults and what it means
Why it was measured
To see whether an ingredient prevents the disease.
Statistical vs. clinical meaning
Ginkgo did not lower dementia in this trial.
Safety implication
Side effects were similar to placebo.
| Study | Result | People | Product |
|---|---|---|---|
| 6 | Dementia HR 1.12 (0.94 to 1.33); Alzheimer HR 1.16; progression from mild impairment HR 1.13 | 3,069 adults aged 75 or older | Ginkgo extract |
Memory test scores
Higher scores in several reviews in trials
Scores on timed word-list, recall and recognition tests.
Low certaintyResults and what it means
Why it was measured
To see whether memory changes with an ingredient or vitamin.
Statistical vs. clinical meaning
Gains differ between ingredients and groups.
Safety implication
Not reported in the abstracts.
Safety
What studies and official sources say about side effects, medicines and who should check first. Each point shows what kind of evidence it comes from.
Main points to know 7
- Labels may not match what is inside. A lab check of 12 brain-health products found 8 (67%) had a label ingredient the lab could not detect, and 10 (83%) held compounds not on the label. A lab check of 22 products listing huperzine A found 16 (73%) with an undetected label ingredient and 16 (73%) with unlabelled compounds; only 2 had huperzine A within 10% of the label. A check of 6 online phenibut products found three had far less than claimed and one far more. These were small, hand-picked samples, not the whole market. Laboratory analysis 3 4 21
- Hidden stimulants and drugs have been found in brain products. The huperzine A study found stimulants not listed on labels, including higenamine, vinpocetine, noopept and hordenine, and 9 of 22 products listed ingredients that do not meet FDA rules for supplements. Phenibut, found in some nootropic products, is a prescription medicine in some countries and has case reports of toxicity and withdrawal. Ask a pharmacist before using any product that lists drug-like ingredients. Laboratory analysis 4 21
- Proprietary blends hide the amount of each ingredient. The FDA labelling guide says a proprietary blend must show its name, its total weight and its ingredients in order of weight. It does not require the amount of each one. So the amount of caffeine, for example, may not be known from the label, and the label cannot be matched to the amounts used in trials. Regulator guidance (verified 2026 10 26) 29
- Stimulants add up. Many brain formulas contain caffeine. The FDA says caffeine amounts in supplements are often given voluntarily, that some medicines and conditions raise sensitivity, and that large amounts can be dangerous. The FDA has cited 400 mg a day as an amount not generally linked to negative effects for most adults. Caffeine from coffee, tea, energy drinks and other products counts as well. Regulator statement (verified 2026 10 26) 28
- Ginkgo and high-amount vitamin E can raise bleeding concerns. NCCIH says some data suggest ginkgo can increase bleeding risk. For vitamin E, high amounts caused bleeding and affected clotting in animals, and lab data suggest they inhibit platelets. Vitamin E may interact with blood-thinning and platelet medicines. Tell a doctor or pharmacist if you take blood thinners or plan surgery. Regulator statement based on limited human, animal and lab data 30
- Alpha-GPC was linked with more strokes in one very large study. In South Korean insurance records of about 12 million adults aged 50 or older, people prescribed alpha-GPC had a higher chance of stroke over 10 years than non-users (aHR 1.43 after matching), rising with longer use. This is an association, not proof of cause. People with stroke risk should ask a doctor before using alpha-GPC products. Observational cohort study 11
- The same nutrient in several products. Brain formulas often hold B vitamins, vitamin E, selenium, calcium or vitamin D. NCCIH says high vitamin B6 intakes of 1 to 6 g a day for 12 to 40 months caused nerve damage in reports, that too much selenium, calcium or vitamin D can harm, and that vitamin D excess is toxic. Check labels of all products you use for the same nutrient and ask a pharmacist to add them up. Regulator statement (verified 2026 10 26) 30
Side effects 6
| Effect | How often | Severity and recovery | Evidence |
|---|---|---|---|
| No serious side effects in L-theanine trials Single ingredient, not a blend. | No serious adverse events reported in a 31-trial review | Not applicable Not applicable | Meta-analysis 7 |
| Headache, nausea, stomach upset, diarrhoea, dizziness or allergic skin reactions (ginkgo) A Cochrane review found serious side effects not more common than placebo in mild cognitive impairment (high certainty). | Not given | Mostly mild; more severe allergic reactions occasionally reported Not stated | Regulator statement 30 |
| Stomach discomfort, headache, allergic reactions (lion's mane) | Not given; often unreported | Not stated Not stated | Systematic review 14 |
| Too much caffeine: negative effects, and danger in large amounts | Varies by person, medicines and conditions | Can be serious Not stated | Regulator statement 28 |
| Higher stroke risk linked with alpha-GPC use Association only. | aHR 1.43 (1.41 to 1.46) after matching | Serious Not applicable | Observational cohort study 11 |
| Nerve damage with long-term very high vitamin B6 intake | Reported at 1 to 6 g a day for 12 to 40 months | Severe and progressive in reports Symptoms usually stop when stopped, per NCCIH | Regulator statement 30 |
Liver
No formula-level liver data were found. NCCIH says very high amounts of curcumin caused liver problems in animals and no human cases were reported. Liver safety of other ingredients was not looked up in LiverTox. 30
How often. No frequency was found.
Monitoring. No agency monitoring advice was found.
This is a safety connection. It is not evidence that Multi-Ingredient Brain Formulas supports liver health.
Medicines and supplements 5
| With | Why it matters | Importance | Evidence | What to do |
|---|---|---|---|---|
| Blood thinners and antiplatelet medicines (with ginkgo or high-amount vitamin E) prescription | NCCIH: some data suggest ginkgo can increase bleeding risk; high amounts of vitamin E affected clotting in animals and lab tests. | Possible increased bleeding. Stated by NCCIH as a concern, not a proven human effect for every product. | Regulator statement based on limited data Low certainty 30 | Tell a doctor or pharmacist. Ask before surgery. |
| Caffeine-sensitive conditions and medicines prescription | The FDA says some medicines and conditions make people more sensitive to caffeine. | More jitteriness, heart or sleep effects may occur. Which medicines were not listed in the page read. | Regulator statement Low certainty 28 | Ask a doctor or pharmacist whether caffeine in a formula suits your medicines. |
| Vitamin B12 and acid-reducing or diabetes medicines prescription | NCCIH: proton pump inhibitors, H2 blockers, metformin and chloramphenicol might lower vitamin B12 levels. | Relevant for formulas containing B12. | Regulator statement Low certainty 30 | Ask a pharmacist. |
| Undeclared stimulants and drug-like ingredients unknown | Some products held stimulants not on the label. | Interactions with heart, blood pressure, mood or ADHD medicines were not studied. | Laboratory analysis; interaction not studied Not enough evidence 4 3 | Absence of a study is not proof of safety. Ask a pharmacist. |
| Other supplements with the same nutrients supplement | Stacking adds up the same nutrient. | See the stacking note under Key safety. | Regulator statement Low certainty 30 | Add up all products with a pharmacist. |
Who should check first 5
| Situation | Advice | Evidence |
|---|---|---|
| Pregnancy and breastfeeding | No safety study of brain formulas in pregnancy or breastfeeding was found in the sources read. The FDA advises talking to a health provider about caffeine if pregnant, trying to become pregnant or breastfeeding. Ask a doctor or midwife before using any blend. | Absence of evidence and regulator statement 28 |
| Children and teens | No trial safety data for brain formulas in children were found. The FDA page notes medical experts advise against energy drinks for children and teens because of sugar and caffeine. Do not give a blend to a child without a doctor's advice. | Absence of evidence and regulator statement 28 |
| Taking blood thinners, or surgery planned | Ginkgo and high-amount vitamin E raise bleeding concerns. Ask a doctor or pharmacist. | Regulator statement 30 |
| ADHD, dementia or memory change | See a clinician first. No supplement here replaces a prescribed medicine. | Clinical caution |
| Stroke risk, heart disease, or high blood pressure | Ask a doctor, because of the alpha-GPC stroke finding and the stimulants in many formulas. | Observational study and regulator statement 11 28 |
Overdose, product quality and regulators
Summary. No poisoning or overdose data for finished brain formulas were found in the sources read. Toxicity depends on each ingredient.
Animal. Not reviewed, apart from NCCIH notes on vitamin E and curcumin in animals.
High dose or long term signals. Long-term safety of daily blend use was not found. NCCIH describes harms from very high vitamin B6, selenium, calcium and vitamin D intakes.
Overdose response. Not found.
Genotoxicity. Not researched.
Label accuracy is the main quality concern. Three small lab studies found missing and unlabelled ingredients. Heavy-metal testing of brain formulas specifically was not found.
Brain-health products picked from the market. 8 of 12 had a label ingredient not detected; 10 of 12 held compounds not on the label. 3
Products listing huperzine A. 16 of 22 had an undetected label ingredient; 16 had unlabelled compounds including stimulants; only 2 had huperzine A within 10% of the label. 4
Online phenibut products. Three of 6 had much less than the label; one had much more; all had undeclared ingredients. 21
| Body | Action | Date |
|---|---|---|
| US Food and Drug Administration (FDA) (United States) | States that the FDA does not have the authority to approve dietary supplements for safety and effectiveness, or approve their labelling, before they are sold. Advises talking to a health professional, and says "natural" does not mean safe. Companies must report serious adverse events to the FDA within 15 days. source | 2022-06-02 |
| US Food and Drug Administration (FDA) (United States) | Caffeine page: cites 400 mg a day as an amount not generally associated with negative effects for most adults; says supplements may add caffeine and often state its amount voluntarily; says some medicines and conditions increase sensitivity. source | 2024-08-28 |
| US Food and Drug Administration (FDA) (United States) | Labelling guide: a proprietary blend is listed by name with its total weight and its ingredients in order of weight. source | 2005-04-01 |
| NCCIH (US National Center for Complementary and Integrative Health) (United States) | Clinician digest: no conclusive evidence for ginkgo in preventing or slowing dementia; no convincing efficacy of omega-3 supplements in mild-to-moderate Alzheimer disease; no evidence vitamin E prevents mild impairment from progressing; B-vitamin results mixed; multivitamins show no clear benefit for cognition in well-nourished people. Lists safety notes for ginkgo, vitamin E, B6, selenium, calcium and vitamin D. source | 2022-07 |
When to get medical help
- Swelling of the face, lips or tongue, hives, wheezing or trouble breathing after a product: call emergency services.
- Sudden weakness or numbness on one side, face drooping, trouble speaking or sudden severe headache: call emergency services.
- Chest pain, a racing or pounding heart, fainting, or severe agitation after a stimulant-containing product: get urgent medical care.
- Unusual bleeding or bruising, black stools, or blood in urine, especially if you take blood thinners: see a doctor.
- Persistent vomiting, severe stomach pain, or tingling or numbness in hands and feet after starting a product: stop it and see a doctor.
Stop using the product and contact a clinician or emergency service. In the US, Poison Control is 1-800-222-1222.
General information only, not medical advice. Ask a clinician or pharmacist before use, especially with medicines, in pregnancy or with a health condition. See the Natural Remedy Safety guide.
Frequently asked questions
What is a multi-ingredient brain formula?
A supplement that mixes several ingredients, such as caffeine, L-theanine, herbs, choline compounds and vitamins, and is sold for memory, focus or mental energy.
Have finished brain formulas been tested?
Does a long ingredient list mean a stronger formula?
Which ingredient has the strongest evidence?
Can I add up the results for each ingredient?
No. Trials tested single ingredients in specific groups, forms and amounts. A finished blend can contain an ingredient at a form or amount nobody tested.
Do ginkgo or omega-3 prevent dementia?
Do multivitamins help memory?
Can the label be wrong?
What is a proprietary blend?
A group of ingredients listed together with a total weight, in order of weight, without the amount of each one. You cannot work out the amount of any single ingredient.
Do these products contain hidden stimulants?
Some did. A lab check of huperzine A products found unlabelled stimulants such as higenamine and vinpocetine in many of 22 products. It was a small sample, not the whole market.
Who should ask a doctor first?
Where do I report a bad reaction?
Tell a doctor or pharmacist first. The FDA also takes reports of problems with dietary supplements.
Explore by health goal
Editorial transparency
- Written by
- AlternativeMed editorial team. Research compiled with AI assistance, then checked against the sources listed.
- Medical review
- None. This page has not been reviewed by a physician or pharmacist.
- First published
- 2026-10-26
- Last substantive update
- 2026-10-26
- How we research
- We started from our existing table of brain-formula ingredients, re-read PubMed abstracts for every review, trial and lab study cited, and read the NCCIH and FDA pages in full. Only abstracts were read for studies. The NIH Office of Dietary Supplements page was blocked and is marked unread.
- How we rate evidence
- See "How we rate evidence" in the Evidence tab.
- Independence
- No product is promoted on this page. No affiliate links are shown. Some trials were paid for by makers or tea companies, and this is flagged where the abstracts show it.
Sources 31
Each source was opened and checked. Where we read only the abstract, it says so. The small numbers in the text point here.
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Where to buy
Check the label first. Whatever you buy, look for these:
- The amount of the active ingredient per serving, not just the front-label claim
- A third-party testing mark (USP, NSF or ConsumerLab)
- Other ingredients and allergens
- Ask a pharmacist about interactions with your medicines
Talk to a pharmacist or doctor before you start any supplement, especially if you take medicines. See the Safety tab for interactions.
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