Nootropics and Memory Supplements Compared: Bacopa, Ginkgo, Lion's Mane and More
Bacopa, ginkgo, lion's mane, caffeine with theanine, creatine and other memory supplements compared by what trials found, in healthy adults versus people with memory conditions.
Content last updated . This page has not been medically reviewed.
Overview
"Nootropic" is a marketing word for products said to help thinking, memory or focus. It is not a medical category. This page compares the products people ask about most and, for each, separates studies in healthy adults from studies in people who already have memory or thinking problems. Those are different questions, and a result in one group should not be assumed for the other.Evidence labels used here: established recommendation (guidelines or consistent trials agree), promising but limited (some positive human trials, small or short), mixed (trials disagree), insufficient evidence (too little human data to judge), preclinical (animal or lab only). "Proper evidence not found" means we looked and could not read adequate human research.
Supplements are not a treatment for memory loss or dementia. The National Institute on Aging warns people to check with a doctor before trying any pill that promises to prevent Alzheimer's, because such products may be unsafe, a waste of money, or may interfere with prescribed treatment. [1]
What research shows
| Product | Healthy adults | People with memory or thinking problems | Label |
|---|---|---|---|
| Caffeine (coffee, tea) | A review of plant-derived substances concluded caffeine enhances attention and executive functions. [2] | Not covered here | Promising but limited for short-term alertness |
| Caffeine plus L-theanine | A 2025 meta-analysis found small differences favoring theanine plus caffeine on some attention and mood tests in the first two hours, with wide uncertainty. [3] | Not covered here | Mixed |
| Bacopa (Bacopa monnieri) | A meta-analysis of 9 trials (518 people, 12 weeks or more) found shorter times on two attention tests. [4] A systematic review found it improved memory free recall on 9 of 17 tests, with little evidence for other abilities. [5] | Not the focus of these reviews | Promising but limited |
| Ginkgo (Ginkgo biloba) | A large trial in 3,069 adults aged 75 and older found no reduction in dementia. [6] | A 2026 Cochrane review found it probably has little or no effect on cognition or daily activities in mild cognitive impairment. [7] | Insufficient evidence for prevention; mixed for dementia treatment |
| Lion's mane (Hericium erinaceus) | A 41-person pilot found a faster Stroop response one hour after one dose, with some null results. [8] | A 30-person trial in Japanese adults aged 50 to 80 with MCI reported higher scores on one scale while taking it, falling after it stopped. [9] | Insufficient evidence: small trials |
| Creatine | A meta-analysis of 8 trials found a small memory improvement versus placebo, strongest in adults aged 66 to 76. [10] | A 2024 meta-analysis of 16 trials mixing healthy people and people with disease found benefits for memory, attention time and processing speed, but not overall cognition. [11] | Promising but limited |
| Phosphatidylserine | A narrative review made strong claims; it was not a systematic review of trials. [12] | One 12-month trial in 190 people with MCI tested a mixed product (plant omega-3, phosphatidylserine, ginkgo flavonoids, B vitamins), so any effect cannot be assigned to phosphatidylserine alone. [13] | Insufficient evidence |
| Omega-3 capsules | Reviews of trials in older people without dementia found no benefit. [14] | No convincing benefit in mild-to-moderate Alzheimer's. [14] | Insufficient evidence (fish in the diet is a separate question) |
| B vitamins | Short-term trials show no help; a meta-analysis of longer trials suggests possible slowing of decline. [14] | A 2018 Cochrane review found no cognitive benefit over 6 to 24 months. [14] | Mixed |
| Vitamin E | Little human data. [14] | A 2017 Cochrane review found no evidence it prevents progression from MCI to dementia. [14] | Insufficient evidence |
| Curcumin | A 12-month trial in 96 healthy older adults found limited effects on cognition. [14] | Clinical trials are few and inconsistent. [14] | Insufficient evidence |
Other "nootropic" blends, stacks and proprietary formulas: Proper evidence not found. We searched PubMed and the NCCIH evidence summary and found human trials only for individual ingredients, not for commercial blends.
Things to keep in mind
- Study amounts are not advice. The ginkgo trial used 120 mg of extract twice a day. [6] Bacopa trials used 300 to 450 mg of extract a day for 12 weeks. [5] A pilot of lion's mane used 1.8 g. [8] A 2026 network meta-analysis of 29 trials in healthy adults reported that high-dose bacopa (600 mg a day or more) improved working memory, but the authors said the lack of direct comparisons limits the strength of that evidence. [15]
- Short lab tasks are not daily life. Many trials measure reaction time or word recall for a few hours. They do not show you will remember appointments better.
- Small trials, sponsors and mixed products make results less certain. Check who paid and how many people took part.
- Mechanism is not proof. Lab findings, such as effects on nerve growth factors, are preclinical until people are tested. [16]
Safety and interactions
- Ginkgo can cause headache, stomach upset, dizziness or allergic skin reactions, and some data suggest it can raise bleeding risk. [14] See Ginkgo and how interactions work.
- Lion's mane side effects are not well reported; a systematic review lists stomach discomfort, headache and allergic reactions as possible. [16] See mushroom safety and mushroom supplements.
- High-dose vitamin B6 over long periods can damage nerves, and vitamin E supplements can interact with blood thinners. [14]
- Tell your doctor and pharmacist about every supplement you take, including ones used rarely. [17] Supplements are also not tested like medicines; see how supplements are regulated.
- Caffeine: the FDA has cited about 400 mg a day (roughly two to three 12-ounce cups of coffee) as an amount not generally associated with negative effects for most adults, but sensitivity varies. [18] See coffee.
When to get help
New or worsening memory problems need evaluation, not a supplement trial. See when to get help and medicines that affect memory.Frequently asked questions
Do nootropics work?
Some single ingredients have small, short-term effects in some trials, such as caffeine for alertness and creatine for memory tests in older adults. [2][10] Most evidence is limited, and none is proven to prevent dementia. [1]
Does ginkgo improve memory?
In a trial of 3,069 older adults, ginkgo did not reduce dementia. [6] A 2026 Cochrane review found little or no effect in mild cognitive impairment. [7]
Is lion's mane proven for memory?
No. Human trials are small, and the results are tentative. [8][9]
Can a supplement prevent Alzheimer's disease?
No supplement has been proven to. Be wary of products that promise it. [1]
Are memory supplements safe with my medicines?
Not always. Ginkgo may raise bleeding risk and vitamin E can interact with blood thinners. [14] Ask a pharmacist. [17]
References
- National Institute on Aging, Preventing Alzheimer's Disease: What Do We Know?. Read 2026-10-22.
- Crit Rev Food Sci Nutr 2023. Plant-derived nootropics and human cognition: a systematic review. Read 2026-10-22.
- Payne ER et al. Nutr Rev 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. Read 2026-10-22.
- Kongkeaw C et al. J Ethnopharmacol 2014. Meta-analysis of randomized controlled trials on cognitive effects of Bacopa monnieri extract. Read 2026-10-22.
- Pase MP et al. J Altern Complement Med 2012. The cognitive-enhancing effects of Bacopa monnieri: a systematic review of randomized, controlled human clinical trials. Read 2026-10-22.
- DeKosky ST et al. JAMA 2008. Ginkgo biloba for prevention of dementia: a randomized controlled trial. Read 2026-10-22.
- Wieland LS et al. Cochrane Database Syst Rev 2026. Ginkgo biloba for cognitive impairment and dementia. Read 2026-10-22.
- Docherty S et al. Nutrients 2023. The acute and chronic effects of lion's mane mushroom supplementation on cognitive function, stress and mood in young adults: a double-blind, parallel groups, pilot study. Read 2026-10-22.
- Mori K et al. Phytother Res 2009. Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment. Read 2026-10-22.
- Nutr Rev 2023. Effects of creatine supplementation on memory in healthy individuals: a systematic review and meta-analysis of randomized controlled trials. Read 2026-10-22.
- Xu C et al. Front Nutr 2024. The effects of creatine supplementation on cognitive function in adults: a systematic review and meta-analysis. Read 2026-10-22.
- Glade MJ, Smith K. Nutrition 2015. Phosphatidylserine and the human brain. Read 2026-10-22.
- J Affect Disord 2025. Effects of a food supplement containing phosphatidylserine on cognitive function in Chinese older adults with mild cognitive impairment: a randomized controlled trial. Read 2026-10-22.
- NCCIH, Dietary Supplements and Cognitive Function, Dementia, and Alzheimer's Disease: What the Science Says (July 2022). Read 2026-10-22.
- Tiemtad P et al. Phytomedicine 2026. Comparative effects of Bacopa monnieri and Ginkgo biloba on cognitive functions: a systematic review and network meta-analysis. Read 2026-10-22.
- Menon et al. Front Nutr 2025. Benefits, side effects, and uses of Hericium erinaceus as a supplement: a systematic review. Read 2026-10-22.
- National Institute on Aging, Taking Medicines Safely as You Age. Read 2026-10-22.
- US Food and Drug Administration, Spilling the Beans: How Much Caffeine is Too Much?. Read 2026-10-22.
Education, not medical advice. This page is for general information. It does not diagnose or treat any condition and is not a substitute for care from a qualified health professional. Natural does not automatically mean safe. Ask a clinician or pharmacist before changing your care, especially if you take medication, are pregnant or breastfeeding, or have a health condition.