What does the research show about ginseng?

Ginseng

Pooled trials found a small drop in fatigue and a trivial effect on erectile function. One meta-analysis found lower fasting glucose and a larger one did not. In cognitive impairment, two meta-analyses report small test-score gains. Physical performance did not change. American ginseng lowered warfarin's effect in a randomized trial. Product ginsenoside content varied up to 36-fold.

Add to Bio HackChecked 2026-11-09

Status: Dietary supplement in the US. Siberian ginseng (Eleutherococcus senticosus) is a different plant and is not covered here.
Also called: Panax ginseng, Asian ginseng, Korean ginseng, red ginseng, Panax quinquefolius, American ginseng, North American ginseng, ginsenosides
Taken for: energy, fatigue, focus, memory, erectile function, blood sugar, immunity, colds, athletic performance

Strong several reviews agree · Moderate one review or consistent trials · Limited one or a few small studies · Untested no study in people, listed with what it rests on

Shown to help4

StrongShown to raise cognition scores slightly in people with cognitive impairment or dementia, below the threshold for clinical significance.
ModerateShown to reduce fatigue modestly in adults with fatigue, including chronic illness, across few small trials.
ModerateShown to raise erectile function scores about 3.5 points on a 30-point scale in men with mild to moderate dysfunction, below the minimal important difference.
LimitedOne trial found fewer colds and fewer cold days over 4 months on a North American ginseng extract in adults prone to colds.

Reported risks2

ModerateShown to lower INR slightly with American ginseng in healthy adults taking short courses of warfarin.How often is not known
LimitedLimited evidence: in 25 US products, ginsenoside content differed from labels, varying up to 36-fold.How often is not known

What people take it for, and what was found

Shown to help4

Strong

Cognition in cognitive impairment or dementia

Shown to raise cognition scores slightly in people with cognitive impairment or dementia, below the threshold for clinical significance.

The numbers and sources

Effect: In 8 RCTs of people with subjective memory impairment, mild cognitive impairment or Alzheimer's disease, ginseng raised MMSE scores by 0.68 points (95% CI 0.03 to 1.32, I² 66%) and lowered ADAS-cog scores by 1.10 points (95% CI -1.82 to -0.38, I² 0%) [1]. In 9 studies of 617 older adults with mild cognitive impairment, Alzheimer's disease or dementia, MMSE rose 0.38 points (95% CI 0.03 to 0.74) and ADAS-cog fell 2.21 points (95% CI -3.97 to -0.44) [2].
Population: Adults with memory or cognitive impairment [1]. 617 older adults with mild cognitive impairment, Alzheimer's disease or dementia [2].
Sources: [1], [2]
Caveats: The authors of [2] report that the gains did not reach the threshold for clinical significance, and note few studies and moderate heterogeneity. MMSE heterogeneity in [1] was 66%. Review [2] searched Chinese databases.

Moderate

Fatigue

Shown to reduce fatigue modestly in adults with fatigue, including chronic illness, across few small trials.

The numbers and sources

Effect: In 4 RCTs pooled, ginseng reduced fatigue (SMD 0.34, 95% CI 0.16 to 0.52) [3]. A systematic review of 10 studies of Asian and American ginseng in people with fatigue found modest evidence of benefit and a low risk of adverse events [4].
Population: Adults with fatigue, including chronic illness [3][4].
Sources: [3], [4]
Caveats: The meta-analysis authors judged the evidence insufficient because trials were few and small [3].

ModerateStudied in men

Erectile function

Shown to raise erectile function scores about 3.5 points on a 30-point scale in men with mild to moderate dysfunction, below the minimal important difference.

The numbers and sources

Effect: In 9 studies of 587 men with mild to moderate erectile dysfunction, ginseng raised IIEF erectile function scores by 3.52 points (95% CI 1.79 to 5.25) on a 30-point scale, below the 4-point minimal important difference, and by 2.39 points (95% CI 0.89 to 3.88) on a 25-point scale. Self-reported ability to have intercourse improved (RR 2.55, 95% CI 1.76 to 3.69) [7].
Population: Men aged 20 to 70, followed up to 12 weeks [7].
Sources: [7]
Caveats: Certainty was low to moderate, and the Cochrane authors describe the effect on erectile function as trivial [7].

Limited

Colds

One trial found fewer colds and fewer cold days over 4 months on a North American ginseng extract in adults prone to colds.

The numbers and sources

Effect: In 279 adults with at least 2 colds in the prior year, an extract of North American ginseng taken for 4 months lowered colds per person (0.68 vs 0.93), the share with 2 or more colds (10.0% vs 22.8%) and days with cold symptoms (10.8 vs 16.5) [8].
Population: Adults aged 18 to 65 in Edmonton, Canada [8].
Sources: [8]
Caveats: One trial of one polysaccharide-rich extract. 44 people who never started treatment were excluded from analysis [8].

Mixed results1

Moderate

Blood sugar

Mixed results: one review found fasting glucose about 0.3 mmol/L lower, and a larger review found no significant effect on blood sugar.

The numbers and sources

Effect: Across 16 trials of 30 days or longer, ginseng lowered fasting blood glucose by 0.31 mmol/L (95% CI -0.59 to -0.03). Fasting insulin, HbA1c and HOMA-IR did not change overall [5]. A 2025 meta-analysis of 70 studies (4,506 participants) on cardiovascular risk factors found no significant effect on the glycemic profile, with a dose-response association for fasting glucose and fasting insulin [6].
Population: 770 people with and without diabetes [5]. 4,506 participants in 70 studies [6].
Sources: [5], [6]
Caveats: The two reviews disagree on fasting glucose. Two thirds of trials in [5] ran under 12 weeks, and most participants already had well-controlled glucose [5].

Not shown to help1

Limited

Cognition in healthy people

Limited evidence: a Cochrane review found no convincing evidence of a cognitive effect in healthy people.

The numbers and sources

Effect: A Cochrane review found 9 trials, 5 with usable data, all in healthy participants. Data could not be pooled. Some aspects of cognition, behavior and quality of life improved, and the authors found no convincing evidence of a cognitive effect in healthy people and no high-quality evidence in dementia [9].
Population: Healthy adults and one trial in age-associated memory impairment [9].
Sources: [9]
Caveats: Search date was 2009 [9].

Doses studied

Trials varied in species, preparation and dose. The glucose meta-analysis included trials of 30 days or longer [5]. The cold trial gave 2 capsules a day of a North American ginseng extract for 4 months [8]. Measured ginsenoside content in US products varied 15-fold in capsules and 36-fold in liquids [10].

Risks

Reported risks2

ModerateHow often is not known

Warfarin interaction

Shown to lower INR slightly with American ginseng in healthy adults taking short courses of warfarin.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: In a randomized trial of 20 healthy adults, 2 weeks of American ginseng lowered peak INR compared with placebo (difference -0.19, 95% CI -0.36 to -0.07), and reduced INR AUC, peak warfarin level and warfarin AUC [12]. The 2002 review lists possible interactions between Panax ginseng and warfarin, phenelzine and alcohol [11].
Population: Young healthy volunteers [12]. Case reports [11].
Sources: [11], [12]
Caveats: Participants took warfarin for 3 days at a time, not as ongoing therapy [12].

LimitedHow often is not known

Product content

Limited evidence: in 25 US products, ginsenoside content differed from labels, varying up to 36-fold.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: In 25 US ginseng products, all were the plant genus they claimed. Ginsenoside content differed from label, varying 15-fold in capsules and 36-fold in liquids. Siberian ginseng marker compounds varied 43-fold in capsules and 200-fold in liquids [10].
Population: Products from one health food store [10].
Sources: [10]
Caveats: One 2001 sample. A systematic search for adulterants was not done [10].

Checked, no increase found1

Moderate

Adverse events in trials and reports

Adverse events were about as common as on placebo with single-ingredient Panax ginseng. Headache, sleep problems and gut complaints were the most common.

The numbers and sources

How common: How often is not known: the sources give no rate.
Effect: Trial data show adverse events with single-ingredient Panax ginseng at rates similar to placebo. Headache, sleep problems and gastrointestinal complaints were the most common. Serious events appear in isolated case reports, mostly with combination products where other ingredients may be responsible [11]. In erectile dysfunction trials, adverse events did not clearly differ from placebo (RR 1.45, 95% CI 0.69 to 3.03) [7].
Population: Trial participants and spontaneous reports [7][11].
Sources: [7], [11]
Caveats: The safety review dates from 2002 [11].

Claims tested and not found

That ginseng improves physical performance. Across 8 RCTs, ginseng did not change physical performance (SMD -0.01, 95% CI -0.29 to 0.27) [3].
That ginseng improves HbA1c or insulin resistance. HbA1c, fasting insulin and HOMA-IR did not change overall across pooled trials [5]. A 70-study review found no significant effect on the glycemic profile [6].

Sources

Kim J, Kang M, Lim H. Cognitive Benefits of Ginseng: A Systematic Review and Meta-Analysis of Changes in Mini-Mental State Examination and Alzheimer's Disease Assessment Scale-Cognitive Subscale Scores. Complementary Medicine Research. 2025. https://doi.org/10.1159/000547543
Chen N, Yu L, Hua Q, et al. Ginseng for Cognitive Function in Elderly Adults with Mild Cognitive Impairment, Alzheimer's Disease, or Dementia: A Systematic Review and Meta-Analysis. Current Neuropharmacology. 2026. https://doi.org/10.2174/011570159X415818251222083130
Bach HV, Kim J, Myung SK, Cho YA. Efficacy of Ginseng Supplements on Fatigue and Physical Performance: a Meta-analysis. Journal of Korean Medical Science. 2016. https://doi.org/10.3346/jkms.2016.31.12.1879
Arring NM, Millstine D, Marks LA, Nail LM. Ginseng as a Treatment for Fatigue: A Systematic Review. The Journal of Alternative and Complementary Medicine. 2018. https://doi.org/10.1089/acm.2017.0361
Shishtar E, Sievenpiper JL, Djedovic V, et al. The Effect of Ginseng (The Genus Panax) on Glycemic Control: A Systematic Review and Meta-Analysis of Randomized Controlled Clinical Trials. PLoS ONE. 2014. https://doi.org/10.1371/journal.pone.0107391
Jafari A, Mardani H, Abbastabar M, et al. The effect of ginseng supplementation on CVD risk factors: a comprehensive systematic review and dose-response meta-analysis. British Journal of Nutrition. 2025. https://doi.org/10.1017/S0007114525103607
Lee HW, Lee MS, Kim TH, et al. Ginseng for erectile dysfunction. Cochrane Database of Systematic Reviews. 2021. https://doi.org/10.1002/14651858.CD012654.pub2
Predy GN, Goel V, Lovlin R, et al. Efficacy of an extract of North American ginseng containing poly-furanosyl-pyranosyl-saccharides for preventing upper respiratory tract infections: a randomized controlled trial. Canadian Medical Association Journal. 2005. https://doi.org/10.1503/cmaj.1041470
Geng J, Dong J, Ni H, et al. Ginseng for cognition. Cochrane Database of Systematic Reviews. 2010. https://doi.org/10.1002/14651858.CD007769.pub2
Harkey MR, Henderson GL, Gershwin ME, et al. Variability in commercial ginseng products: an analysis of 25 preparations. The American Journal of Clinical Nutrition. 2001. https://doi.org/10.1093/ajcn/73.6.1101
Coon JT, Ernst E. Panax ginseng: a systematic review of adverse effects and drug interactions. Drug Safety. 2002. https://doi.org/10.2165/00002018-200225050-00003
Yuan CS, Wei G, Dey L, et al. Brief Communication: American Ginseng Reduces Warfarin's Effect in Healthy Patients. Annals of Internal Medicine. 2004. https://doi.org/10.7326/0003-4819-141-1-200407060-00011

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