Can Nootropics Increase IQ? What the Smart-Drug Trials Show
Can nootropics increase IQ? No trial shows it. In healthy adults, ginkgo's effect on memory is near zero, and piracetam and Bacopa evidence is weak.
Dr. Russell T. WarneChief Scientist
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No nootropic has been shown to increase IQ. In the best summary for healthy adults, a meta-analysis of 13 ginkgo trials found an effect on memory of d = -0.04, which is less than one IQ point and in the wrong direction.
"Nootropic" is a marketing umbrella for pills, powders and herbs sold to sharpen thinking. Most have never been tested on an IQ test at all, and the ones that have been tested in placebo-controlled trials show effects that are small or absent. This page covers what the label means, what the trials for piracetam, ginkgo and Bacopa found, why the "IQ boost" claim keeps circulating, and how supplements are regulated. Prescription stimulants are a separate question, covered in our page on whether Adderall raises IQ. This page describes research and is not medical advice.
What counts as a nootropic?
The pharmacologist Corneliu Giurgea set out a "nootropic" approach to brain pharmacology in the early 1970s, and piracetam, sold under the brand name Nootropyl, was the first drug of the class. Today the label covers almost anything sold as a "brain booster": synthetic "racetams" related to piracetam, herbal extracts such as ginkgo and Bacopa, amino acids such as L-theanine, vitamins, and blends of all of these. Some people also use the word for prescription stimulants and wakefulness drugs, which have their own evidence base.
Masud Husain and Mitul Mehta, reviewing cognitive enhancers in health and disease, concluded that experimental and clinical studies had shown "relatively modest overall effects", most probably because people vary so much in how they respond. Their review was mostly about prescription drugs. The over-the-counter products sold as nootropics usually have even less behind them.
It also helps to be clear about what a claim to "increase IQ" would require. An IQ test samples many abilities (reasoning, vocabulary, memory, spatial skill and processing speed) and summarises them as one score. A product that slightly speeds reaction time on one computer task has not raised IQ. To raise IQ, it would need to lift performance broadly, in a well-designed trial, on tests the person had not simply practised.
What the trials show for popular nootropics
Piracetam and the racetams
Piracetam is the original nootropic. A small 1976 double-blind study by Dimond and Brouwers gave piracetam to healthy volunteers and reported better verbal learning after 14 days, but not after 7. That study is still quoted in marketing, but it was a single word-list task, and it has not grown into a body of evidence in healthy people.
Most later piracetam research was in older adults with dementia or cognitive impairment. A Cochrane review by Leon Flicker and John Grimley Evans found that piracetam improved clinicians' "global impression of change" (pooled odds ratio 3.55), but the evidence on cognition itself was inconclusive. They concluded that the published evidence did not support its use in dementia. Newer racetams sold online (aniracetam, phenylpiracetam and others) have even less human data.
Ginkgo biloba
Ginkgo is the best-tested herbal nootropic, and the results are consistently null.
• Healthy older adults: In a six-week trial by Paul Solomon and colleagues, 230 adults over 60 took ginkgo or placebo according to the manufacturer's instructions. There were no significant differences on any measure of learning, memory, attention, concentration or verbal fluency, nor in how the participants or their companions rated their memory.
• Healthy younger adults: Canter and Ernst reviewed 15 randomised trials in people under 60 and found "no convincing evidence" for a robust effect on any aspect of cognition. Positive findings in single-dose studies appeared on scattered outcomes at particular times and doses and were not replicated.
• The meta-analysis: Laws and colleagues pooled trials in healthy people and found effect sizes of d = -0.04 for memory (13 trials, 1,132 participants), -0.05 for executive function and -0.08 for attention. Multiplying d by 15 converts it to IQ-style points, so all three are within about one point of zero.
• The prevention trial: The Ginkgo Evaluation of Memory study randomised 3,069 adults aged 75 or older to ginkgo or placebo for a median of 6.1 years. Ginkgo did not reduce dementia (hazard ratio 1.12, 95% CI 0.94 to 1.33) and did not slow decline in memory, attention, language, spatial skill or executive function.
Bacopa monnieri
Bacopa, a herb from Ayurvedic medicine, has the most encouraging results of the three. Kongkeaw and colleagues pooled nine randomised trials of at least 12 weeks (518 participants). Bacopa shortened completion times on the Trail Making Test B, a task that requires switching attention, and choice reaction times. The authors described this as potential to improve "speed of attention", and said a large, well-designed trial would be needed for definitive evidence. Faster attention on two tasks is a long way from a higher IQ, and no Bacopa trial I am aware of has reported a full-scale IQ score.
Caffeine and L-theanine
Caffeine with L-theanine, often called a "stack" in nootropic forums, produces short-lived gains in alertness and attention. A meta-analysis by Camfield and colleagues found moderate effects in the first two hours after a dose, and changing the caffeine dose mattered more than changing the L-theanine dose. That is a real but temporary state effect. The question of whether green tea makes you smarter has its own page, because tea delivers both compounds in one cup.
Why the "IQ boost" claim persists
The cultural template is the 2011 film Limitless, in which a pill turns a struggling writer into a genius. Real cognitive enhancement looks nothing like that, but the film gave supplement marketing a story to borrow.
The evidence base also lends itself to selective quotation. Many small trials measure dozens of outcomes. A chance improvement on one task at one time point can be quoted on a label, even when the main results were null and the finding never replicated, which is exactly the pattern Canter and Ernst described for ginkgo.
Regulation leaves room for this. In the United States, the FDA states that it does not approve dietary supplements or their labelling before they are sold, so a product can claim to "support memory" without trial evidence. When a company crosses into disease claims, the FDA can act: in a 2019 warning letter, it told one online nootropics seller that claims made for products including piracetam and ginkgo, such as treating dementia, made them unapproved new drugs.
What is inside the bottle is a further problem. Pieter Cohen and colleagues bought 10 cognitive-enhancement supplements labelled as containing racetams and found five drugs not approved for human use in the United States, including omberacetam, aniracetam and phenibut. Some drugs were undeclared, 9 of 12 declared quantities were inaccurate, and a single product could expose a user to up to four unapproved drugs at doses up to four times a typical pharmaceutical dose.
Confounds and why IQ is hard to move
Nootropic users are not a random sample, so survey reports that they feel sharper tell us little. People who choose to take a cognitive supplement may differ from those who do not in education, motivation, health habits and expectations, and expectation alone can colour how someone rates their own focus. That is why only blinded, placebo-controlled trials with objective tests count as evidence here.
Age and baseline health matter too. A product that helps someone who is ill or short of sleep may do nothing for someone who is healthy and rested. The ginkgo trials covered both healthy young adults and older adults, and neither group benefited.
Finally, IQ in adults is a broad and fairly stable trait. The few supplements with a plausible effect, such as creatine in vegetarians, show small gains on specific tasks under specific conditions. The broader evidence on what does and does not move scores is summarised in our guide to whether you can increase your IQ.
Frequently asked questions
Do nootropics actually work?
Some produce small, short-term effects on specific tasks, mostly through caffeine. None has been shown in controlled trials to raise general intelligence or IQ in healthy people.
Is piracetam legal in the United States?
Piracetam is not an FDA-approved drug, and the FDA has treated products marketed with disease claims for it as unapproved new drugs. Rules differ by country, so check local regulations and ask a doctor or pharmacist.
Does ginkgo biloba improve memory?
Not in healthy people. A meta-analysis found effects on memory, attention and executive function close to zero, and a six-year trial in older adults found no protection against dementia or cognitive decline.
Are nootropics safe?
Safety depends on the product, and testing has found supplements containing unapproved drugs and inaccurate doses. Anyone considering a supplement, especially alongside other medicines, should talk to their doctor or pharmacist first.
Can a supplement make you a genius like in Limitless?
No. The largest effects seen in real trials are a few milliseconds of reaction time or small changes on single tasks, far from the sweeping change the film depicts.
The takeaway
The nootropic shelf promises more than the trials deliver. Ginkgo, the best-studied herb, does nothing measurable for memory or attention in healthy people; piracetam's evidence is old and thin; Bacopa shows modest gains in attention speed on a couple of tasks. None has been shown to raise IQ, and some products contain unapproved drugs. If you want an accurate picture of your reasoning ability, take an online IQ test built by psychometricians.
References
1. Laws, K. R., Sweetnam, H., & Kondel, T. K. (2012). *Is Ginkgo biloba a cognitive enhancer in healthy individuals? A meta-analysis*. Human Psychopharmacology: Clinical and Experimental, 27(6), 527-533. [doi.org/10.1002/hup.2259](https://doi.org/10.1002/hup.2259)
2. Husain, M., & Mehta, M. A. (2011). Cognitive enhancement by drugs in health and disease. Trends in Cognitive Sciences, 15(1), 28-36. doi.org/10.1016/j.tics.2010.11.002
3. Giurgea, C. (1973). The "nootropic" approach to the pharmacology of the integrative activity of the brain. Conditional Reflex, 8(2), 108-115. doi.org/10.1007/BF03000311
4. Dimond, S. J., & Brouwers, E. Y. M. (1976). Increase in the power of human memory in normal man through the use of drugs. Psychopharmacology, 49(3), 307-309. doi.org/10.1007/BF00426834
5. Flicker, L., & Grimley Evans, J. (2004). Piracetam for dementia or cognitive impairment. Cochrane Database of Systematic Reviews, CD001011. doi.org/10.1002/14651858.CD001011
6. Solomon, P. R., Adams, F., Silver, A., Zimmer, J., & DeVeaux, R. (2002). Ginkgo for memory enhancement: A randomized controlled trial. JAMA, 288(7), 835-840. doi.org/10.1001/jama.288.7.835
7. Canter, P. H., & Ernst, E. (2007). Ginkgo biloba is not a smart drug: An updated systematic review of randomised clinical trials testing the nootropic effects of G. biloba extracts in healthy people. Human Psychopharmacology: Clinical and Experimental, 22(5), 265-278. doi.org/10.1002/hup.843
8. DeKosky, S. T., Williamson, J. D., Fitzpatrick, A. L., Kronmal, R. A., Ives, D. G., Saxton, J. A., Lopez, O. L., Burke, G., Carlson, M. C., Fried, L. P., Kuller, L. H., Robbins, J. A., Tracy, R. P., Woolard, N. F., Dunn, L., Snitz, B. E., Nahin, R. L., & Furberg, C. D. (2008). Ginkgo biloba for prevention of dementia: A randomized controlled trial. JAMA, 300(19), 2253-2262. doi.org/10.1001/jama.2008.683
9. Snitz, B. E., O'Meara, E. S., Carlson, M. C., Arnold, A. M., Ives, D. G., Rapp, S. R., Saxton, J., Lopez, O. L., Dunn, L. O., Sink, K. M., & DeKosky, S. T. (2009). Ginkgo biloba for preventing cognitive decline in older adults: A randomized trial. JAMA, 302(24), 2663-2670. doi.org/10.1001/jama.2009.1913
10. Kongkeaw, C., Dilokthornsakul, P., Thanarangsarit, P., Limpeanchob, N., & Scholfield, C. N. (2014). Meta-analysis of randomized controlled trials on cognitive effects of Bacopa monnieri extract. Journal of Ethnopharmacology, 151(1), 528-535. doi.org/10.1016/j.jep.2013.11.008
13. Cohen, P. A., Avula, B., Wang, Y.-H., Zakharevich, I., & Khan, I. (2021). Five unapproved drugs found in cognitive enhancement supplements. Neurology: Clinical Practice, 11(3), e303-e307. doi.org/10.1212/CPJ.0000000000000960
14. Camfield, D. A., Stough, C., Farrimond, J., & Scholey, A. B. (2014). Acute effects of tea constituents L-theanine, caffeine, and epigallocatechin gallate on cognitive function and mood: A systematic review and meta-analysis. Nutrition Reviews, 72(8), 507-522. doi.org/10.1111/nure.12120
Hero image: Ginkgo biloba (7), by Marija Gajić, CC BY-SA 4.0. Via Wikimedia Commons.
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