Panax ginseng (Asian or Korean ginseng) may help a little with some things, but you should not expect a big payoff. It is a root used in traditional Chinese medicine, and the better-supported results are small improvements in some blood markers, blood-vessel function, general fatigue and erectile function. Most trials are small and short, and several disagree with each other. For athletic performance the research mostly shows no benefit, and for anxiety, asthma or aging there is too little to say.
Quick facts
| Item | What the research shows |
|---|---|
| Forms | Root, usually sold as powder or extract. ‘Red’ and ‘white’ ginseng are the same species prepared two ways (NCCIH). |
| Compounds of interest | Ginsenosides, thought to be the most important active substances. |
| Doses used in studies | One supplement-review site summarizes trial doses of 200-400 mg a day of a standardized extract, with some fatigue trials using about 2 g a day. NCCIH gives no single dose. |
| Typical study length | Most trials last under 3 months and enroll fewer than 200 people (NCCIH). Some cognition studies measure effects within hours of one dose. |
| Main studied uses | Blood markers and vascular function, fatigue, erectile dysfunction, thinking skills, blood sugar, flu, exercise recovery. |
Does Panax ginseng actually work?
It might, modestly, but nothing about it is settled. NCCIH, part of the U.S. National Institutes of Health, says larger studies lasting longer than 3 months are needed. Many of the results below are lab measures rather than how you feel or function, a distinction explained in our guide to surrogate outcomes in trials. The pooled studies are meta-analyses, which our guide to meta-analyses and systematic reviews explains.
What have human studies found?
Blood markers of heart and metabolic health
Two large pooled analyses of randomized trials point in somewhat different directions.
- A 2025 meta-analysis of 70 studies with 4,506 participants found lower C-reactive protein (an inflammation marker), a liver enzyme (GGT), and oxidative-stress markers. It found no significant effects on blood pressure, blood sugar measures, cholesterol, body measurements or heart rate.
- A 2024 meta-analysis of 45 randomized trials found small average drops in systolic blood pressure (about 2.6 mmHg), total cholesterol (about 4.4 mg/dL), LDL cholesterol (about 2.8 mg/dL), C-reactive protein and interleukin-6. The authors noted high heterogeneity, meaning the trials disagreed with each other, and called for higher-quality studies.
So the two reviews disagree on blood pressure and cholesterol, and the changes in the second are small. Neither shows that ginseng prevents heart disease.
Blood-vessel function
A 2025 meta-analysis of 13 randomized trials found ginseng was linked with better flow-mediated dilation (how well your arteries widen) and lower pulse wave velocity (a measure of arterial stiffness). It found no change in augmentation index, another stiffness measure. The authors recommended further studies.
Fatigue
If you are tired in general, ginseng alone may help a little. NCCIH describes a 2023 review of 19 studies (2,413 participants) that found a small benefit for general fatigue not tied to a disease. For chronic fatigue, the benefit was seen with herbal formulas containing other ingredients, not ginseng alone, and not all research agrees. A 2022 review of ginseng in chronic fatigue syndrome, quoted in a patient-forum post, found only two eligible studies with 68 patients and concluded that no firm conclusions could be drawn.
Erectile dysfunction (ED)
Ginseng looks promising for ED, but it is not a proven fix. NCCIH says some research shows oral Asian ginseng seems to improve sexual function in people with ED, and one small study in men with an enlarged prostate suggested it may improve some aspects of sexual function. One supplement-review site summarizes pooled trials (including a 7-trial analysis) as favoring red ginseng over placebo, while noting low study quality and small samples. You will not find a head-to-head comparison with a prescribed ED drug here, so nothing supports using ginseng in place of one. If ED is your concern, a clinician can look for underlying causes.
Thinking skills
Expect subtle effects at most. NCCIH says a small amount of research suggests improvements in abstract thinking, attention, arithmetic and reaction time in middle-aged adults but not young adults. Any memory benefit appeared to depend on adding ginkgo. The same review site describes a Cochrane review as calling the evidence suggestive but not conclusive, because of small samples and design limits.
Blood sugar and diabetes
The results are mixed. NCCIH describes a 2022 review of 20 studies (1,295 participants) in prediabetes and diabetes that found improvements in fasting glucose, total cholesterol and some inflammatory markers, but says research on blood sugar control in people with diabetes is overall inconclusive and conflicting. A 2025 review of how ginseng might act on diabetes at the cell level reported that almost all research is limited to animal and cell experiments. The 70-study analysis above found no significant effect on its overall blood sugar measures.
Flu and immunity
Treat this as unsettled. NCCIH says a very small amount of preliminary research suggests ginseng extract may help reduce the risk of getting flu, but not the severity or length of symptoms. Results are described as inconsistent elsewhere.
Exercise and athletic performance
Don’t count on a boost. NCCIH says the majority of research shows ginseng does not improve athletic performance. A 2024 systematic review of six trials on muscle damage after resistance exercise found conflicting results and some bias in every study, and concluded that ginseng does not appear to reduce markers of that damage.
Anxiety, asthma, aging
NCCIH says there is not enough reliable information to say whether ginseng helps with these.
Does ginseng raise cortisol or boost estrogen?
The human studies above measured things like C-reactive protein and cholesterol, not cortisol or hormone levels, so there is no cortisol answer to give you. NCCIH notes that ginseng is called an adaptogen, meaning a herb thought to help the body resist stress. That is a traditional idea, not a measured cortisol result. On estrogen, one supplement-review site says ginseng showed weak estrogen-like activity in some laboratory studies and advises caution with hormone-sensitive conditions. That is lab data, not proof of an effect in people.
If you are worried about high cortisol, what the signs are, or how to test for it, that is a separate question from ginseng. A clinician can decide whether testing makes sense and which test fits your situation.
What doses did researchers use?
These are amounts from studies, not advice. The supplement-review site summarizes trials as using 200-400 mg a day of a standardized extract (4-7% ginsenosides), with benefits in some cognition studies appearing within hours of a single dose and other outcomes measured after 4-12 weeks. It also says some fatigue trials at about 2 g a day showed stronger effects than lower doses. The 70-study analysis ran dose-response models and linked dose to several markers (fasting glucose, C-reactive protein, diastolic blood pressure, fasting insulin), but its abstract does not name an ideal dose. Trials differ in form and extract, so numbers from one study may not carry over to the product in your hand. A clinician or pharmacist can help you judge what fits you.
Is ginseng safe? Side effects and interactions
For most people, taking it by mouth for a short time, up to 6 months, in recommended amounts appears safe, according to NCCIH. Long-term safety has been questioned.
| Issue | What NCCIH says |
|---|---|
| Most common side effect | Insomnia |
| Uncommon reports | Severe rash, liver damage, severe allergic reactions |
| Blood sugar | Might lower blood sugar; people with diabetes should consult a provider first |
| Blood clotting | May interfere with clotting |
| Autoimmune disorders | May worsen them |
| Medicines | May interact with certain medicines, sometimes harmfully |
| Pregnancy and breastfeeding | Some studies suggest oral use may be unsafe in pregnancy; one chemical in it caused birth defects in animals. Little is known about breastfeeding. Some experts advise against use in infants and children. |
| On the skin | Not enough information on safety; may cause irritation and burning |
The supplement-review site also lists blood thinners, diabetes drugs and MAO-inhibitor antidepressants among medicines to discuss with a clinician first.
Who should talk to a clinician first?
- Anyone taking a prescription or over-the-counter medicine, especially for diabetes, blood clotting or depression.
- People with diabetes, an autoimmune disorder or a bleeding problem.
- People who are pregnant, breastfeeding or planning pregnancy, and parents thinking about it for children.
- People with hormone-sensitive conditions.
- Anyone with a procedure coming up, since ginseng may affect clotting.
Ginseng is not a replacement for a prescribed medicine, and any change to your medicines is a decision for your prescriber.
What questions are still open?
- Whether benefits last beyond about 3 months, and how safe it is past 6 months.
- Which form, extract or dose works best, since trials use different products.
- Whether the small shifts in lab markers lead to fewer heart attacks or other results you can feel.
- Whether it affects cortisol, hormones, anxiety, asthma or aging.
For help sorting label claims from research, see our guide to ingredient evidence versus marketing claims.
How do you read a ginseng supplement label?
- Species name. Look for Panax ginseng. American ginseng (Panax quinquefolius) is a different species, and Siberian ginseng (Eleutherococcus senticosus) is a different plant with a different body of evidence, according to the review site.
- Form. Root powder, extract, red or white preparation. An extract’s weight is not the same as root weight, so compare like with like.
- Ginsenoside percentage. The review site notes that if a label gives only raw root weight, you cannot tell how much active compound you are getting. Studies often use standardized extracts.
- Proprietary blends. If ginseng sits in a blend with only a total weight listed, you cannot tell how much ginseng you are getting, so you cannot compare it with study doses.
- Quality checks. The review site says market surveys have found ginseng products with no detectable ginsenosides or with contaminants. NCCIH notes supplements are not approved by the FDA before sale, and makers are responsible for their own safety and labeling. An independent third-party testing mark on the label is one useful clue.
Before you order
- Does the label state the species and form, and is the amount per serving clear?
- Is the ginsenoside percentage listed, and is there any outside testing?
- Have you checked with a clinician or pharmacist about your medicines and conditions?
By ClinicalStudyConnect.com Research Desk