July 2019 Issue

Botanicals/Herbs: Nootropics — Do They Really Boost Brain Function?
By Ginger Hultin, MS, RDN, CSO
Today’s Dietitian
Vol. 21, No. 7, P. 12

Supplements that improve memory, attention, and cognition are gaining in popularity not just among those suffering from Alzheimer’s disease (AD) and other forms of dementia but also among healthy adults. This category of chemicals and botanicals are called nootropics or, colloquially, “smart drugs.”1 Research has found improved outcomes for those with cognitive impairment due to natural aging or AD/dementia, but there’s some evidence that nootropics can help people of any age for a variety of reasons.

With consumer interest in nootropics skyrocketing, manufacturers are responding in kind—so much so that the Federal Trade Commission issued a public warning earlier this year regarding some supplement manufacturers’ extreme and unsubstantiated health claims, such as that the supplements can cure AD, heart disease, Parkinson’s disease, and even cancer.2

Botanical Options
Following is an exploration of some of the most common, best known, and most studied botanical/herbal supplements marketed as nootropics. Overall, some supplements do show promise for improving brain function and can be considered nootropics, but RDs should caution clients and make them aware of any safety concerns and the lack of conclusive scientific evidence.

Bacopa monnieri (brahmi): This Ayurvedic herb is used to improve memory and intelligence.3 Studies on bacopa extracts for improving cognitive function are mixed, with some showing potential improvements in reactivity time but not in working memory, learning rate, or recognition of pictures and words.4 With no significant side effects reported in clinical studies when used for as long as 12 weeks, it has shown efficacy for reducing nervousness, palpitations, insomnia, headache, lack of concentration, fatigue, anorexia, tremors, and irritability in patients with anxiety. Bacopa also has shown some improvement in children with ADHD.

Several moderate drug-nutrient interactions can occur between bacopa and cytochrome P450 medications such as cholinergic drugs, haloperidol (Haldol), clozapine (Clozaril), celecoxib (Celebrex), warfarin (Coumadin), some antifungals, and some chemotherapeutic agents, among others.4

Ginkgo biloba: Commonly used in extract form for treating AD, dementia, and other age-related aspects of mental decline, ginkgo may produce modest improvements in certain types of memory in some people, but research is mixed.3 Recent studies suggest that it may be the anti-inflammatory benefits ginkgo provides that contribute to this potential improvement.5

Ginseng (Panax ginseng/American ginseng and Eleutherococcus senticosus/Siberian ginseng): Though there are many species of ginseng, American and Siberian varieties most commonly are used as nootropics. Kelly Morrow, MS, RDN, FAND, an associate professor and nutrition clinic coordinator at Bastyr University and the Bastyr Center for Natural Health, explains that clinical results are conflicting, possibly due to differing ginsenoside concentrations and doses used in research.

Clinical evidence that American and Siberian ginseng can improve cognitive function in young and middle-aged adults and seniors exists, and benefits, including improved abstract thinking, attention, and working memory as tested by mental math, and better reaction times, have been observed.3,6,7

There’s a possibility that ginseng can improve cognitive performance in patients with AD, but results have been inconsistent.3 Some studies show that bioactive compounds in ginseng may play a role in β-amyloid levels in the brain (a marker of AD),8 but Maggie Moon, MS, RD, author of The MIND Diet, says, “It’s important to note there is no known cure or reversal of the disease progression of Alzheimer’s at present, just an improvement of symptoms.”

Gotu kola: Related to parsley, gotu kola is a tropical plant used to treat fatigue, anxiety, and depression, and improve memory, cognitive function, AD, and epilepsy.9 Research is mixed and relatively weak, with the majority being small human studies and animal studies. Furthermore, many studies used combinations of gotu kola and other nootropics such as DHA, making the effect of gotu kola alone difficult to determine.3

Rosemary: Diterpenes, active compounds in rosemary, may have some therapeutic potential when it comes to benefitting cognition overall and even improving AD symptoms.10-13 Mary Purdy, MS, RDN, host of the podcast and video broadcast Mary’s Nutrition Show and past chair of the Dietitians in Integrative and Functional Medicine Dietetic Practice Group, says, “Even just the smell of rosemary has been seen in some small studies to provide positive effects on mood and the nervous system.” In the study she cites, participants reported feeling more alert and content, with objective improvements in brain electrical activity, blood pressure, heart and respiratory rate, and skin temperature.14 Purdy recommends roasting veggies with rosemary sprigs to easily incorporate this herb and potential nootropic.

St. John’s wort: This herb has been used for hundreds of years to treat conditions such as depression. St. John’s wort is a natural monoamine oxidase inhibitor (MAOI) and selective serotonin reuptake inhibitor (SSRI), both of which slow down reuptake of neurotransmitters such as serotonin and gamma-aminobutyric acid to create a calming and antidepressive effect. Studies show that it’s more effective than placebo and, in some cases, even as effective as antidepressant medications in mild to moderate depression.15,16

Though St. John’s wort is a nootropic, Morrow warns, “When it comes to depression, I usually steer away from recommending St. John’s wort and defer to doctors. There are many ways we can help people with depression using diet and lifestyle factors.” St. John’s wort has the most drug-nutrient interactions of any common herb, she explains. “It dramatically speeds up CYP 3A4, one of the cytochrome enzymes in the liver and gut that processes many drugs, increasing the effects of the drug. It’s also contraindicated in those already taking SSRIs and MAOIs due to an additive effect and increased risk of toxicity and serotonin syndrome. Many people don’t know the risks of St. John’s wort, as there are no required warning labels,” Morrow says.

Turmeric: Studies suggest that the active compound in turmeric, curcumin, may act as a neuroprotective antioxidant, reducing inflammation and boosting mood, especially in cognitive decline, dementia, or other mood disorders.17-19 One study clearly showed improvement in working memory and mood with regular curcumin treatment.17 A meta-analysis showed possible efficacy in improving depressive symptoms with no adverse events reported, but many improvements have been insignificant compared with placebo.20

“I certainly think it’s well worth an experiment and have seen supplements work effectively for many patients, particularly for reducing inflammation,” Purdy says. She suggests using turmeric in the diet rather than via supplements, such as grating it into a marinade, adding it to a stir-fry or smoothie, blending it into coleslaw, puréeing it into soup, eating curry, or making golden milk out of turmeric powder, warm nondairy milk, and honey or stevia.

Moon isn’t yet convinced about the use of turmeric as a nootropic, but she also recommends culinary use. “The evidence is too mixed to know if turmeric is effective for boosting cognition,” Moon says. “Some supplement studies have come up empty against placebos in high-functioning groups, while others find improvement after long-term use.”21

Safety and Scope of Practice
Dietitian experts have many words of caution when it comes to nootropics. “The complexity of real food can’t be captured in a pill, and, while some supplements show promise as nootropics, others don’t,” Moon says. Her advice, like Purdy’s, is to incorporate some of these herbs into the diet. “Nootropics are found in real foods, and, when this is the case—the risk is nonexistent and there’s any level of potential benefit—there doesn’t seem to be any harm to adding them to your shopping cart,” Moon says.

In her discussion of St. John’s wort, Morrow brings up a critical question: “Is it prudent for an RDN to recommend an herb with such strong pharmacologic activity? Can we be sure that a person needs to boost their serotonin, or is this better decided by a physician or psychiatrist?” Dietitians should keep in mind that while nootropics do show promise for cognitive activity, it may be prudent to refer patients to specialists to ensure their safety.

Dietitians should do thorough research before using nootropics in practice to understand when to guide patients away from using them, especially if they’re taking the place of validated treatment options. Read up on the evidence using a credible source such as the Natural Medicines Database before considering these for patients. Assess the risk vs potential benefit to provide patients with the best information possible. Always consider referring patients who are curious about nootropics to a qualified integrative dietitian who has expertise in this area.

The bottom line? Though research on nootropics continues to emerge, there are many safety considerations before RDs can recommend these products.

— Ginger Hultin, MS, RDN, CSO, is a nutrition and health writer and certified specialist in oncology nutrition based in Seattle. She’s past chair of the Vegetarian Nutrition Dietetic Practice Group, past president of the Chicago Academy of Nutrition and Dietetics, and owner of concierge nutrition practice, Champagne Nutrition LLC.


1. Phenibut. Natural Medicines Database website. https://naturalmedicines.therapeuticresearch.com/databases/food,-herbs-supplements/professional.aspx?productid=1184. Updated February 13, 2019. Accessed May 4, 2019.

2. FTC and FDA send warning letters to companies selling dietary supplements claiming to treat Alzheimer’s disease and remediate or cure other serious illnesses such as Parkinson’s, heart disease, and cancer. Federal Trade Commission website. https://www.ftc.gov/news-events/press-releases/2019/02/ftc-fda-send-warning-letters-companies-selling-dietary. Published February 11, 2019. Accessed May 3, 2019.

3. Enhancing memory and mental function. ConsumerLab.com website. https://www.consumerlab.com/tnp.asp?chunkiid=35549. Updated December 5, 2015. Accessed May 3, 2019.

4. Bacopa. Natural Medicines Database website. https://naturalmedicines.therapeuticresearch.com/databases/food,-herbs-supplements/professional.aspx?productid=761. Updated February 12, 2019. Accessed May 4, 2019.

5. Sharma M, Fitzpatrick AL, Arnold AM, et al. Inflammatory biomarkers and cognitive decline: the Ginkgo Evaluation of Memory Study. J Am Geriatr Soc. 2016;64(6):1171-1177.

6. Reay JL, Scholey AB, Kennedy DO. Panax ginseng (G115) improves aspects of working memory performance and subjective ratings of calmness in healthy young adults. Hum Psychopharmacol. 2010;25(6):462-471.

7. Reay JL, Kennedy DO, and Scholey AB. Single doses of Panax ginseng (G115) reduce blood glucose levels and improve cognitive performance during sustained mental activity. J Psychopharmacol. 2005;19(4):357-365.

8. Razgonova MP, Veselov VV, Zakharenko AM, et al. Panax ginseng components and the pathogenesis of Alzheimer’s disease (review). Mol Med Rep. 2019;19(4):2975-2998.

9. Gotu kola. Natural Medicines Database website. https://naturalmedicines.therapeuticresearch.com/databases/food,-herbs-supplements/professional.aspx?productid=753. Updated February 13, 2019. Accessed May 5, 2019.

10. Habtemariam S. The therapeutic potential of rosemary (Rosmarinus officinalis) diterpenes for Alzheimer’s disease. Evid Based Complement Alternat Med. 2016;2016:2680409.

11. Kennedy DO, Scholey AB. The psychopharmacology of European herbs with cognition-enhancing properties. Curr Pharm Des. 2006;12(35):4613-4623.

12. Nematolahi P, Mehrabani M, Karami-Mohajeri S, Dabaghzadeh F. Effects of Rosmarinus officinalis L. on memory performance, anxiety, depression, and sleep quality in university students: a randomized clinical trial. Complement Ther Clin Pract. 2018;30:24-28.

13. Moss M, Cook J, Wesnes K, Duckett P. Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults. Int J Neurosci. 2003;113(1):15-38.

14. Sayorwan W, Ruangrungsi N, Piriyapunyporn T, Hongratanaworakit T, Kotchabhakdi N, Siripornpanich V. Effects of inhaled rosemary oil on subjective feelings and activities of the nervous system. Sci Pharm. 2013;81(2):531-542.

15. Linde K, Berner MM, Kriston L. St John’s wort for major depression. Cochrane Database Syst Rev. 2009;(4):CD000448.

16. Apaydin EA, Maher AR, Shanman R, et al. A systematic review of St. John’s wort for major depressive disorder. Syst Rev. 2016;5(1):148.

17. Cox KH, Pipingas A, Scholey AB. Investigation of the effects of solid lipid curcumin on cognition and mood in a healthy older population. J Psychopharmacol. 2015;29(5):642-651.

18. DiSilvestro RA, Joseph E, Zhao S, Bomser J. Diverse effects of a low dose supplement of lipidated curcumin in healthy middle aged people. Nutr J. 2012;11:79.

19. Small GW, Siddarth P, Li Z, et al. Memory and brain amyloid and tau effects of a bioavailable form of curcumin in non-demented adults: a double-blind, placebo-controlled 18-month trial. Am J Geriatr Psychiatry. 2018;26(3):266-277.

20. Ng QX, Koh SSH, Chan HW, Ho CYX. Clinical use of curcumin in depression: a meta-analysis. J Am Med Dir Assoc. 2017;18(6):503-508.

21. Rainey-Smith SR, Brown BM, Sohrabi HR, et al. Curcumin and cognition: a randomised, placebo-controlled, double-blind study of community-dwelling older adults. Br J Nutr. 2016;115(12):2106-2113.