This is our library of nootropic ingredients. Each guide explains what the ingredient is, what human research actually shows (and where it’s thin), the doses used in clinical studies, side effects, drug interactions and how to buy a quality product. Every health claim links to its source, usually PubMed or the NIH Office of Dietary Supplements.
New to nootropics? Start with What Are Nootropics?, then browse by goal below.
Nootropic Ingredients By Goal
GoalIngredients To Read About
Calm Focus And StressL-Theanine, Rhodiola Rosea, Ashwagandha, Saffron, Kanna
Attention And Mental EnergyCaffeine, Citicoline, L-Tyrosine, Panax Ginseng, Creatine
Memory And LearningBacopa Monnieri, Phosphatidylserine, Ginkgo Biloba, Huperzine A, Alpha-GPC
Long-Term Brain HealthLion’s Mane, B Vitamins, Maritime Pine Bark, Uridine
Sleep And RecoveryMagnesium L-Threonate, Apigenin, L-Theanine
Energy, Vitality And HormonesTongkat Ali, Panax Ginseng, Rhodiola Rosea
Popular Ingredient Comparisons
Alpha-GPC Vs Citicoline
NALT Vs L-Tyrosine
Phosphatidylserine Vs Phosphatidylcholine
Suntheanine Vs L-Theanine
Ashwagandha Vs Rhodiola
L-Theanine And Caffeine
How We Evaluate Ingredients
We weight human randomized controlled trials and meta-analyses above animal and cell studies, compare commercial doses with the doses used in research, and call out industry funding and small sample sizes. Ratings run from Strong to Preliminary. Nothing here is medical advice. Please read our medical disclaimer and talk with your doctor before starting a supplement.
Alpha-GPC is a highly concentrated choline source studied for power output and for cognition in older adults with memory problems. Here is what the trials show, how to dose it and how to read the 2021 stroke-risk study.
Apigenin is a plant flavone found in chamomile and parsley that became a popular sleep supplement through health podcasts. Here is what the evidence actually shows, and where it runs out.
An evidence-based look at ashwagandha extracts (KSM-66, Sensoril, Shoden), the doses used in stress and sleep trials, and the real safety concerns, including liver injury, thyroid effects and pregnancy.
Vitamins B6, B9 (folate) and B12 are essential for nerve function and homocysteine metabolism. Supplements clearly help people who are low, but trials in people with normal levels show little effect on memory or focus.
Bacopa monnieri is an Ayurvedic herb with modest, mixed evidence for memory recall after 8–12 weeks at about 300 mg a day of a standardized extract. Here is what the trials show, how to dose it and who should avoid it.
Caffeine is the world’s most-used nootropic. Here is what it does for focus, how caffeine pills compare with coffee and energy drinks, and how to use it safely.
Citicoline, also called CDP-choline and sold as Cognizin, supplies both choline and cytidine. Small industry-funded trials suggest modest benefits for attention and memory at 250 to 500 mg a day.
Creatine monohydrate, best known for muscle, has modest but real evidence as a nootropic: meta-analyses show small memory gains, most clearly in older adults and under stress such as sleep loss. It is one of the safest supplements studied.
Ginkgo biloba is one of the best-studied herbal supplements, and most large trials are disappointing: no dementia prevention, no memory boost in healthy people and no proven tinnitus relief. Here is what the evidence does and does not show.
Huperzine A is a plant alkaloid that blocks the enzyme that breaks down acetylcholine. Most of its evidence comes from small, low-quality Alzheimer’s trials, and there is no good evidence it boosts memory in healthy people.
