Nootropics: What the Evidence Says, Ingredient by Ingredient

Nootropics are substances marketed to support memory, focus or mental performance. The term covers prescription drugs such as modafinil, unapproved synthetics such as racetams, and supplement ingredients like caffeine, bacopa, ashwagandha and lion's mane. It is a marketing category rather than a legal or medical one, and the evidence varies widely between ingredients.

There is no evidence-based ranking that fits everyone. We compare ingredients on the size and quality of human trials, label accuracy and safety signals instead. Effects reported in healthy adults are generally modest, and many branded blends have never been tested as formulated. Our brand guide favours fully disclosed formulas and third-party testing.

It depends on the substance. Most supplement-type nootropics are legal to sell, but modafinil is a Schedule IV prescription drug, FDA says piracetam cannot be sold as a dietary supplement, and adrafinil has no FDA approval. Some ingredients face restrictions abroad: Denmark banned ashwagandha in food supplements in 2023.

Safety depends on the ingredient and on product quality. FDA does not review supplements before sale, and a 2019 JAMA Internal Medicine study found unapproved piracetam in 8 of 10 cognitive supplement samples tested. Liver injury has been reported with some botanicals, including ashwagandha. Talk to a pharmacist or doctor before combining nootropics with medication.

A few small trials, including a 30-person study in older Japanese adults with mild cognitive impairment, reported changes in cognitive test scores, but the effects faded after intake stopped and the studies are short and inconsistent. No mushroom supplement is approved to treat cognitive decline. Our lion's mane coverage details each trial and its limits.