By Dr. Mercola
Ginseng is one of the most popular herbal supplements in the US, perhaps most well known for its traditional use of boosting memory and energy levels. However, it has many other uses. For starters, ginseng is considered an adaptogen, which means it helps your body to withstand mental and physical stress.
Delving further into the benefits first requires understanding the different types of ginseng available. There are three major varieties, each with unique attributes, although only two are actually ginseng:
- American ginseng (Panax quinquefolius): This tan, gnarled root contains ginsenosides, which are thought to be responsible for many of its medicinal properties. Chinese medicine, which has used ginseng for thousands of years, considers American ginseng a "cool" calming tonic.1
- Asian ginseng (Panax ginseng): Sometimes referred to as Korean ginseng, Asian ginseng also contains ginsenosides, although in different proportions than American ginseng, and is considered an adaptogenic herb. According to Chinese medicine, Asian ginseng is a "hot" stimulant.2
- Siberian ginseng (Eleutherococcus senticosus): Siberian ginseng is not a true ginseng and does not contain ginsenosides. Its active components are called eleutherosides, which are thought to stimulate your immune system.
Like American and Asian ginseng, however, Siberian ginseng is an adaptogen that's traditionally been used to increase energy, stimulate the immune system, and increase longevity.3
What Are the Health Benefits of American Ginseng?
American ginseng cannot be used for medicinal purposes until it's at least six years old (the wrinkles around the neck of the root reveal its age). Due to overharvesting, American ginseng is endangered in the wild and quite expensive to purchase, although it's also grown on farms now as well.4
Most research to date has involved Asian ginseng, however the studies that have been done on the American variety suggest it may boost your immune system, function as an antioxidant and also benefit inflammatory conditions. It may also be useful as an all-around stress tonic. According to research published in the Journal of Herbs, Spices & Medicinal Plants:5
"[American] Ginseng is traditionally reputed to regularize bodily functions and relieve many ailments resulting from physiological stress. Beneficial effects are thought to be due to a non-specific influence on production and use of regulatory hormones.
As an 'adaptogen', ginseng exhibits anti-fatigue, anti-stress, and anti-aging activity, as well as general improvement of mental and physical performance, 'recognized in therapeutic claims permitted by a plethora of international regulatory constituencies."
Additional benefits include:
Memory: American ginseng was found to improve working memory and mood in both young individuals and middle-age adults.6
Another study revealed "robust working memory enhancement following administration of American ginseng."7
Diabetes: American ginseng appears to have anti-diabetic properties. In one animal study, extract of American ginseng root lead to weight loss and lower blood sugar levels in mice with type 2 diabetes.8
It's also been shown to increase insulin sensitivity in healthy individuals.9
Cancer: American ginseng has anti-cancer properties that appear to suppress tumor growth. It has shown particular promise in treating colorectal cancer.10 Cold and Flu: Older adults who took an extract of American ginseng had a 48 percent reduction in relative risk, and a 55 percent reduction in duration, of respiratory illness.11
This herb was also found to be "a safe and effective treatment for reducing the absolute risk of recurrent colds and the mean number of colds per person."12
ADHD: A combination of American ginseng and ginkgo biloba may improve symptoms of attention deficit hyperactivity disorder (ADHD) in children and teens.13 Immune System Function: American ginseng has also been found to stimulate the immune system, helping your body fight off infections and disease.14
What Are the Health Benefits of Asian Ginseng?
If you're wondering which type of ginseng is right for you, consider this: if you're seeking an herb to calm stress-related problems, American ginseng is the "cooling" or "calming" version of the two. Asian ginseng is regarded as heating and is not generally recommended for stress relief.
Differences in levels of the eight major ginsenosides are thought to account for the plants' varying characteristics. For example, Asian ginseng contain similar quantities of the ginsenosides Rb1 and Rg1, while American ginseng has very little Rg1. Rg1 is regarded as a central nervous system (CNS) stimulant, fatigue fighter, enhancer of mental performance.
For comparison, Rb1 is a CNS depressant with tranquilizing and anti-psychotic properties. As written in the journal Phytochemistry:15
"Since American ginseng has a lower ratio of Rg1/Rb1, it seems to calm the CNS. In contrast, Asian ginseng appears to stimulate the CNS."
Also, while American ginseng appears promising for type 2 diabetes, the results are less clear for Asian ginseng. While some research suggests a benefit for diabetes, other studies have found it could raise blood sugar levels, so this is an area that needs further study.16 With that in mind, what else might Asian ginseng be beneficial for?
Heart health: Ginseng shows promise for protecting heart health, including anti-hypertensive effects and protection against heart failure.17 Asian ginseng, in particular, may protect against symptoms of heart disease and support healthy cholesterol levels.
Heart health is another area where the effects of Asian and American ginseng need to be further explored, as each likely had different heart effects.
Some research suggests Asian ginseng increases blood pressure at typical doses but lowers it at higher doses, so be careful with its use if you have high blood pressure.18
Neurodegenerative diseases: Evidence is accumulating that Asian ginseng may have neuroprotective properties, including maintaining homeostasis and anti-inflammatory, antioxidant, anti-apoptotic, and immune-stimulatory activities.
The herb could potentially be useful for Parkinson's disease, Alzheimer's disease, Huntington's disease, multiple sclerosis, and other neurological disorders.19
Stroke: Asian ginseng's antioxidant and anti-inflammatory properties appear useful as a promising neuroprotective strategy in stroke.
According to a study published in Frontiers in Cellular Neuroscience, "It can… prevent neuronal death as a result of stroke, thus decreasing anatomical and functional stroke damage. "20
Cancer-related fatigue (CRF): CRF is the most common symptom in patients with cancer. Those who used high-dose Asian ginseng (800 mg orally daily for 29 days) reported improved fatigue, quality of life, appetite and sleep quality.21 Cancer: According to research published in the Alternative Medicine Review, "The mechanisms whereby Asian ginseng is thought to have a potential role as a cancer preventive and treatment agent include the mitigation of DNA damage, anti-inflammatory carcinogenesis, antioxidant chemoprevention, apoptosis induction, inhibition of cancer cell proliferation, and immunomodulation.
Studies have shown the capability of ginseng to repair and reverse cell differentiation in hepatoma, melanoma, and adenocarcinoma cells …
Asian ginseng has shown promise in the treatment of several specific types of cancer, including leukemia, melanoma, and colon, gastric, hepatic, kidney, ovarian, prostate, and pulmonary cancers."22
Cold and flu: Like American ginseng, Asian ginseng appears to stimulate the immune system. In one study, those who took 400 mg of Asian ginseng daily for four months had fewer colds, and those they did come down with were shorter in duration.23 Erectile dysfunction: Asian ginseng may be beneficial in treating erectile dysfunction,24 and it may also improve sperm production, sexual activity, and sexual performance. Mental performance: Asian ginseng appears to boost alertness as well as thinking and learning.
According to the University of Maryland Medical Center, "Early research shows that Asian ginseng may improve performance on such things as mental arithmetic, concentration, memory, and other measures."25
Menopausal symptoms: There is some evidence suggesting Asian ginseng may help relieve certain menopausal symptoms, particularly depression and well-being.26
What Is Siberian Ginseng Used For?
As mentioned, Siberian ginseng is not true ginseng, although it is often confused with the herb. The main uses of Siberian ginseng are immune-system stimulation, to increase energy and vitality and also as an adaptogenic herb used during times of stress.
Siberian ginseng has also been found to have anti-viral properties, and reduced the number of herpes outbreaks among people with the herpes simplex virus type 2.27 Germany's Commission E has approved Siberian ginseng "as a tonic for invigoration and fortification in times of fatigue and debility or declining capacity for work and concentration. Ginseng was also approved for use during convalescence."28
Tips for Using Ginseng
Short-term use of ginseng is considered to be safe among adults. Asian ginseng is best taken in cycles, such as every day for two to three weeks, then taking a break for two to three weeks. In choosing a supplement, fermented ginseng may provide faster, more consistent absorption compared to non-fermented varieties. And if you choose Asian ginseng, look for the unpeeled variety (sometimes called red ginseng), as it will retain more of its bioactive compounds.
While generally safe, if taken in high doses, ginseng may lead to nervousness or insomnia. You should also use caution using ginseng if you're pregnant or breastfeeding, or if you're taking certain medications, including:29
- Diabetes medications
- Blood-thinning medications such as warfarin
- Antidepressants called MAOIs (monoamine oxidase inhibitors)
- Anti-psychotic medications or stimulants