Today’s Dietitian
Vol. 27 No. 8 P. 30
Like many other dietary supplements, herbal supplements (HSs) continue to receive enormous attention from competitive and recreational athletes. The hope of enhanced performance coupled with the mistaken belief that plant-derived substances offer an additional layer of safety helps to inflate the appeal and popularity of these loosely regulated products. Dietitians who work with athletic populations are constantly fielding queries and have the difficult yet crucial task of educating on the actual science.
“With the rise of supplement marketing, especially in the field of athletics, I commonly hear questions about the effectiveness and efficiency of different supplements. Athletes are often looking for the things to gain the edge on their opponents and many look to supplements to do this,” says Reilly Beatty, MS, RD, CSSD.
Sport dietitian Kelly Jones, MS, RD, CSSD, is also noticing an uptick in expressed interest about HSs with all types of clientele. “Herbal supplement questions are on the rise with athletes as well as adults focused on health and wellness,” she says.
“I am asked more about supplements than virtually anything else,” shares Chris Mohr, PhD, RD, of Mohr Results Inc. “It is as if everyone is holding out hope for that magic bullet to help them recover more quickly, improve their strength, speed, or anything else,” Mohr adds.
HSs are derived from herbal products extracted from various plant and fungus-based sources, including seeds, gums, roots, leaves, bark, berries, flowers, and mushrooms. Adaptogenic herbs are a subcategory which includes plant or mushroom derivatives that may help the body adapt to stressors via a variety of pathways.1
According to industry data, sales of HSs exceeded $12.5 billion in 2023, and the industry shows no signs of slowing down.2 According to data published in 2022, 50% of the US population uses herbal products and believes that they are safer than medications. Many also report purposefully not disclosing HS use to their health care providers.3,4
Evaluation of Herbal Supplements
Like other dietary supplements, HSs are not strictly regulated. They can be obtained without a prescription and may contain one or more herbal ingredients. HSs can be administered in various ways, including pills, capsules, powders, tinctures, topical treatments, and teas—all sold at major retailers and online vendors. The Dietary Supplement Health and Education Act of 1994 established guidelines indicate that HSs are subject to investigation after products go to market, leaving many improperly dosed, contaminated, and intentionally or unintentionally adulterated. Herbal products often further contribute to the confusion as they are often considered “natural” or “from nature” by consumers, sparking the misconception that this makes them safe by default.
Research is limited in the supplement space but there is data to support that labeling on products often does not accurately reflect their contents and may have inconsistencies in dosing across brands and individual product lines. There are also great risks to health associated with side effects and interactions with prescription medications.
Researchers highlight a series of documented adverse reactions associated with HSs including hallucinations, convulsions, cerebral hemorrhage, perforation of the gastrointestinal tract, congestive heart failure, renal failure, liver damage, respiratory arrest, and cancer.5
There is also evidence that HSs are often contaminated with fungi, heavy metals, and other substances not intended as part of the formulation. In another study, researchers tested duplicate containers of 29 different herbal products and discovered differences in potency relative to label specifications as well as contaminants in an overwhelming majority of products.6
Due to the lack of reliability, it is essential that dietitians recommend products that have undergone third-party testing via organizations commonly used by sports dietitians, such as NSF Certified for Sport and Informed Sport. This can help ensure label accuracy and absence of banned substances but does not ensure safety from adverse interactions or excessive intake, and therefore the risk is mitigated but remains.
Herbal Supplement Hit List
While decisions about the use of HSs should always be customized to the individual after a proper assessment by a qualified professional, here is a short list of HSs that have some evidence to support their use in performance and recovery enhancement in certain doses and settings.
Curcumin
You can thank the adaptogen curcumin for the vibrant, golden color of turmeric powder, and when it comes to performance, this phenolic compound also earns accolades.
When compared with placebo, oral curcumin supplementation reduced creatine kinase and inflammatory cytokines linking it to improved recovery via its ability to reduce inflammation.7 “For athletes with joint pain or osteoarthritis, rather than using turmeric, supplementing with curcumin and piperine may be beneficial,” Jones says. “Curcumin is the polyphenol in turmeric with anti-inflammatory benefits for joint pain and muscle recovery at certain doses. While all athletes should speak with their doctor and dietitian first, it’s recommended to take between 500 and 2,000 mg, depending on the form, along with 5 mg of piperine per 500 mg to enhance bioavailability.”
Cordyceps
Not a plant but a fungus, the cordyceps mushroom was traditionally grown on an insect host but is now often cultivated using grains like oats or rice. This adaptogen continues to gain attention as well as a growing body of evidence to support its use in performance enhancement. “The most interesting research surrounding cordyceps involves how it may improve endurance and energy,” Mohr says. Experimental research supports improved endurance in marathon runners after 12 weeks of supplementation.8
There is also evidence of an increased cardiovascular response in healthy adult runners at a dose of 2 g per day.1,7An animal study published in 2020 determined that cordyceps may enable increased adenosine triphosphate production, which may delay the onset of muscle fatigue.9 A 2016 study found that acute supplementation (one to three weeks) of a mushroom blend including cordyceps elicited improved tolerance to high intensity cycling; authors speculate chronic use may yield improved results.10 While doses of 2 g per day appear to be safe based on the literature, there is a risk of stomach upset at higher doses.
Rhodiola
This perennial herb has been used in Chinese medicine for generations, but data on athletic performance is still limited. Jones cites data published in 2022 highlighting the potential role of rhodiola for performance: “A systematic review and meta-analysis found that rhodiola may benefit exercise performance by reducing muscle damage from training, reducing oxidative stress, and improving explosive power movements.”11 While interesting, more research is needed to determine the effects of taking this product long term. “While no adverse effects were reported in this review, research on rhodiola is still new, so I advise athletes to consider if they notice actual benefits personally and if not, whether their efforts may be better used on other nutrition or recovery habits,” Jones adds. Rhodiola is contraindicated with several medications including blood thinners, antidiabetic drugs, and immunosuppressants; other reported side effects include dizziness and dry mouth.12,13
Ginger
Ginger root has long been touted for its digestive benefits and there is some data to support its use with an athletic population. Doses of less than 5 g per day carry a low risk of side effects. Small studies have linked ginger usage in athletes to reduced muscle soreness and decreased biomarkers of inflammation.1 A study published in 2018 evaluated the benefit of five-day, 1.425 g dosed ginger root supplementation on male and female runners and determined that there was a small reduction in muscle soreness compared with placebo. 14 A 2020 study of 32 runners given a supplement containing ginger and artichoke extracts combined with simethicone reported reductions in both upper and lower GI disturbances. While more research is needed to support use of ginger and ginger containing supplements for GI issues during training, it may be a relatively low-risk strategy to explore for athletes suffering from GI distress.15
Overhyped Supplements
The list of overhyped supplements stretches far and wide, but there is a pool of popular products athletes ask about most often. In some cases, these HSs lack compelling evidence for efficacy, but they may also carry higher risks of side effects and negative interactions with medications.
Ashwagandha
This adaptogenic herb is everywhere. From pills and powders to energy drinks and lip balm. There are claims surrounding ashwagandha and performance but is there science to back it up? There are several factors to consider. “Ashwagandha may be overhyped, especially for those participating in endurance sports and/or who often experience GI upset during training,” Jones says.
Athletes are already at a higher risk of GI discomfort, and according to the NIH, common side effects of ashwagandha include upset stomach and loose stools.16 While considered safe for short term use, evidence is lacking on safety of regular intake past three months” she adds. Therapeutic dosing for ashwagandha use also remains unclear as researched dosing ranges from 120 mg to 12,000 mg.
Berberine
According to Beatty, berberine has gained popularity on social media since it is advertised as a “Natural GLP-1.” This may appeal to athletes, as many report a desire to lose weight, even when it is not warranted. Evidence for using berberine for weight loss in healthy individuals is lacking and it may have a dangerous impact on blood sugar levels.17
Hormone “Boosters”
Athletes are drawn to products that promise to “boost” hormone levels. Both male and female athletes may be looking for HSs to help with hormonal issues they may be experiencing. “Our period recovery athletes usually ask about vitex and chasteberry for ‘hormonal support’” Beatty says. Collegiate sports dietitians often encounter male athletes tempted to use products that promise to “boost” testosterone and human growth hormone, such as tongkat ali and tribulus. Both products lack evidence, plus they pose additional risks because hormones and metabolic modulators are considered banned substances by organizations including NCAA and the World Anti-Doping Agency.18,19
Turmeric
While curcumin may have benefits, turmeric also gets much attention. “Turmeric is an overhyped supplement, particularly due to a lack of understanding of how turmeric is linked to reductions in inflammation, as well as doses needed for benefits” Jones says. “When searching for anti-inflammatory benefits for joint health, picking a random turmeric supplement or using the spice in smoothies can be a waste of money and effort as it isn’t offering efficacious doses, even if consumed multiple times in a day.” She says it is believed that turmeric supplements may not contain an impactful amount of curcumin compared with the isolated curcumin supplements available.
Ginseng
The use of ginseng for athletes is puzzling. While it is one of the most studied HSs, evidence on how it impacts performance is mixed. Examine.com database cites 12 studies using Panax ginseng for athletic performance. Of these evaluations, 10 found no effect while the other two found only small changes in body fat as well as lactate decrease with a very small number of subjects.20 These small potential benefits are likely outweighed by the numerous risks from side effects and substance interactions. Side effects of ginseng use include diarrhea, insomnia, headaches, cardiac issues, and hormonal changes in women. There are also several interactions with medications and other substances including insulin, blood thinners, and caffeine—which is a banned stimulant, and yet heavily used by athletes.
St. John’s Wort
Promoted as an herbal remedy for depression and other mood disorders, athletes suffering from mental health struggles may be interested in taking St. John’s Wort. Using this HS may put athletes at risk for doping violations, as well as a long list of side effects including dizziness, drowsiness, fatigue, and upset stomach. This herbal product also has an alarmingly long list of potential interactions with medications, most noticeably hormonal contraceptives, antidepressants, bronchodilators, and blood thinners.21,22
Resources for Athletes
In a landscape filled with misinformation, compelling advertising and countless unqualified experts, athletes are encouraged to seek guidance from trusted resources who can help them determine whether an HS is the right choice for them. There are five things that dietitians can encourage athletes to do before they consider taking an HS (See sidebar).
The Bottom Line
There is no magic pill that allows for shortcuts, herbal or otherwise. The risks of using most HSs appears to outweigh the benefits, especially for drug tested athletes. While there are some HSs that show promise, it remains imperative that their utilization be from a trusted and tested source.
“To put it simply, no supplement will ever fix improper fueling no matter the athlete,” Beatty advises. “If an athlete is participating in fasted workouts, skipping post workout fuel, and not focusing on meeting their energy needs, they will never see the full benefit of any supplement even if it is backed by research.”
— Dana Angelo White, MS, RD, ATC, is a dual registered dietitian nutritionist and certified athletic trainer with over 20 years of clinical experience. She is a media dietitian, cookbook author, and full-time professor and sports RDN at Quinnipiac University in Hamden, Connecticut.
ATHLETE CHECKLIST: Before Taking an Herbal Supplement
1. Discuss any herbal product with a qualified professional, ideally consult a sports dietitian with supplement expertise. If access to a sports RD is limited, seek out another member of the sports medicine team where basic supplement knowledge is within scope of practice, such as an athletic trainer or strength and conditioning coach with a CSCS credential, to help shape next steps.23
2. Check to see if the specific product has been third-party tested for banned substances using the NSF Certified for Sport or Informed Sport websites or app. Both these platforms allow athletes to search by brand name or product type.
3. Don’t fall for the hype—if a product sounds too good to be true, it usually is!
4. Disclose all medications and supplements used to your medical providers to help prevent the chance of adverse effects or interactions.
5. Self-educate using reliable resources including Sports and Human Performance Nutrition Dietetic Practice Group of the Academy of Nutrition and Dietetics, the American Sports and Performance Dietitians Association, the United States Anti-Doping Agency, and Drug Free Sport International.
References
1. Sellami M, Slimeni O, Pokrywka A, et al. Herbal medicine for sports: a review. J Int Soc Sports Nutr. 2018;15:14.
2. Smith T, Lang C, Craft E. US sales of herbal supplements increase 4.4% in 2023. HerbalGram. 2024;141:54-69. https://umb.herbalgram.org/media/jk4f3rzm/hg141-hmr-web.pdf. Accessed July 30, 2025.
3. Williams CT. Herbal supplements: precautions and safe use. Nurs Clin North Am. 2021;56(1):1-21.
4. Ramirez LI, Kanwugu ON, Ivantsova MN. Impact of herbal supplements nowadays: an overview. ChimTechActa. 2022;9(2S):202292S4.
5. Başaran N, Paslı D, Başaran AA. Unpredictable adverse effects of herbal products. Food Chem Toxicol. 2022;159:112762.
6. Veatch-Blohm ME, Chicas I, Margolis K, Vanderminden R, Gochie M, Lila K. Screening for consistency and contamination within and between bottles of 29 herbal supplements. PLoS One. 2021;16(11):e0260463.
7. Amir M, Vohra M, Raj RG, Osoro I, Sharma A. Adaptogenic herbs: a natural way to improve athletic performance. Health Sci Rev. 2023;7:100092.
8. Savioli FP, Zogaib P, Franco E, Alves de Salles FC, Giorelli GV, Andreoli CV. Effects of Cordyceps sinensis supplementation during 12 weeks in amateur marathoners: a randomized, double-blind placebo-controlled trial. J Herb Med. 2022;34:100570.
9. Choi E, Oh J, Sung GH. Beneficial effect of Cordyceps militaris on exercise performance via promoting cellular energy production. Mycobiology. 2020;48(6):512-517.
10. Hirsch KR, Smith-Ryan AE, Roelofs EJ, Trexler ET, Mock MG. Cordyceps militaris improves tolerance to high-intensity exercise after acute and chronic supplementation. J Diet Suppl. 2017;14(1):42-53.
11. Lu Y, Deng B, Xu L, Liu H, Song Y, Lin F. Effects of rhodiola rosea supplementation on exercise and sport: a systematic review. Front Nutr. 2022;9:856287.
12. Rhodiola: uses, side effects, and more. WebMD website. https://www.webmd.com/vitamins/ai/ingredientmono-883/rhodiola#interactions. Accessed July 30, 2025.
13. Rhodiola. National Center for Complementary and Integrative Health website. https://www.nccih.nih.gov/health/rhodiola. Updated April 2025. Accessed July 30, 2025.
14. Wilson PB. A randomized double-blind trial of ginger root for reducing muscle soreness and improving physical performance recovery among experienced recreational distance runners. J Diet Suppl. 2020;17(2):121-132.
15. Drobnic F, Fonts S, García-Alday I, et al. Efficacy of artichoke and ginger extracts with simethicone to treat gastrointestinal symptoms in endurance athletes: a pilot study. Minerva Gastroenterol (Torino). 2022;68(1):77-84.
16. Ashwagandha: is it helpful for stress, anxiety, or sleep? Office of Dietary Supplements website. https://ods.od.nih.gov/factsheets/Ashwagandha-HealthProfessional/. Updated May 2, 2025. Accessed July 30, 2025.
17. Berberine and weight loss: what you need to know. National Center for Complementary and Integrative Health website. https://www.nccih.nih.gov/health/berberine-and-weight-loss-what-you-need-to-know. Updated November 2023. Accessed July 28, 2025.
18. NCAA banned substances. NCAA website. https://www.ncaa.org/sports/2015/6/10/ncaa-banned-substances.aspx. Updated June 24, 2025. Accessed July 29, 2025.
19. World anti-doping agency prohibited list. USADA website. https://www.usada.org/athletes/substances/prohibited-list/. Accessed July 29, 2025.
20. Supplement guides. Examine website. https://examine.com/guides/. Accessed July 29, 2025.
21. Fonmboh JD, Fokunang EAT, Rose NM, et al. Antidoping concept of play clean to win clean: implication of herbal supplements uses for athletes in competitive sports. J Adv Med Med Res. 2021;33(22):39-58.
22. St. John’s wort. National Center for Complementary and Integrative Health website. https://www.nccih.nih.gov/health/st-johns-wort. Updated May 2025. Accessed July 29, 2025.
23. Lambert V, Carbuhn A, Culp A, Ketterly J, Twombley B, White D. Interassociation consensus statement on sports nutrition models for the provision of nutrition services from registered dietitian nutritionists in collegiate athletics. J Athl Train. 2022;57(8):717-732.
