What is Astragalus Membranaceus?
Astragalus membranaceus, commonly known as huáng qí (Chinese) or milk vetch, is a flowering plant native to Northern China and Mongolia. It has been used for centuries in traditional Chinese medicine. The dried root is the primary part used medicinally.
Astragalus contains various active compounds, including saponins, polysaccharides and flavonoids. The main bioactive components are believed to be the polysaccharides, which have been studied extensively in recent decades.
Benefits and Uses
Immune System Support
Astragalus has been used traditionally to help support and stimulate the immune system. The polysaccharides and flavonoids it contains are thought to account for its immunomodulating effects. Specifically, research shows Astragalus can increase phagocytosis (immune cells engulfing pathogens), encourage T-cell and macrophage activity and raise immunoglobulin levels.
Multiple clinical studies also support the use of Astragalus to help reduce the frequency and duration of upper respiratory tract infections. As such, it is commonly used as a preventative measure during winter.
Anti-Inflammatory Effects
The saponins, flavonoids and polysaccharides in Astragalus also display significant anti-inflammatory capabilities. Scientific research shows they inhibit several pro-inflammatory mediators in the body, including NF-kB and various cytokines.
Human studies provide further evidence of Astragalus’ anti-inflammatory effects, with both oral supplements and injected extracts reducing inflammatory marker levels in patients with systemic inflammation or chronic asthma.
Heart Health
Early research shows Astragalus supplements can help improve some heart health parameters, though more clinical studies are needed.
In diabetic patients and people with heart conditions, Astragalus appears to lower blood pressure, increase ejection fraction, improve ECG readings and relieve symptoms of angina. These effects may result from Astragalus’ anti-inflammatory and anti-oxidative capacities.
Kidney Function
Astragalus has a long history of use alongside conventional treatments to help protect the kidneys in patients with various kidney diseases. Both animal and human studies show detectable improvements in kidney function markers with Astragalus supplementation.
Proposed mechanisms include reducing inflammation and oxidation in kidney tissues, regulating cytokine production from kidney cells and decreasing urea/creatinine levels.
Blood Sugar Control
A number of cell studies demonstrate Astragalus extracts can stimulate glucose uptake and improve insulin sensitivity. Rodent studies also show reduced blood glucose levels in diabetic test subjects after oral Astragalus administration alone or alongside diabetic drugs.
Small human trials report similar findings, with Astragalus supplements alone or with prescription medication lowering fasting blood glucose in diabetic patients. Larger scale studies are still needed however.
Liver Health
Via its anti-inflammatory and antioxidant effects, Astragalus shows promise for providing hepatoprotective (liver-protecting) benefits.
Animal research reveals significant reductions in liver enzymes, inflammatory biomarkers and oxidative damage in liver tissue across multiple models of chemically-induced chronic liver disease. There is also some early evidence for fibrosis prevention.
Is Astragalus Safe?
When used appropriately, Astragalus is very safe for most people. There are a few considerations though:
- Autoimmune conditions: Some doctors advise caution when using Astragalus if you have an autoimmune disorder. Due to its effects on the immune system, there are concerns it may worsen symptoms in some autoimmune conditions. Seek medical advice first in these cases.
- Immunosuppressant medication: People taking immunosuppressant drugs after an organ transplant should avoid Astragalus due its potential immunostimulating effects.
- Bleeding disorders: Astragalus may increase the risk of bleeding/bruising so caution is warranted if you have a bleeding disorder or take blood-thinning medication. Discontinue use prior to any surgical procedures.
- Side effects: When taken at recommended doses, side effects are generally mild (gastrointestinal symptoms) or non-existent. Astragalus is very well tolerated by most people.
Typical Doses
The following daily doses are commonly used, though exact dosing can vary between products:
- Dried sliced root: 9 - 15 grams per day
- Granular root extract: 500 mg - 1 gram
- Liquid tinctures: 30 - 60 drops, 1-3 times per day
As always, follow supplement label directions and consult your health practitioner if unsure of the suitable dosage.
Does Quality Matter?
When sourcing Astragalus supplements, quality is very important. As a general rule:
1. Seek supplements standardised for polysaccharide content. The immunomodulating polysaccharides are seen as the most therapeutically-relevant components. Many products now quantify the polysaccharide content per dose.
2. Choose reputably-branded products tested for purity and potency. Independent analysis from reputable third-party laboratories can verify the active ingredients listed on the label are indeed present as claimed. Contaminant testing also ensures no heavy metals, pesticides or other undesirables are present.
3. Seek organic products using the main root, not just leaves or stems. The dried root is regarded as the most potent part. Organic is preferable to avoid residual pesticides.
When sourced carefully from reputable brands, Astragalus supplements can provide all the proposed benefits outlined above. As with any herbal ingredient though, quality can vary enormously between products so choose wisely.
Frequently Asked Questions
1. Does Astragalus boost energy levels?
While there isn’t much evidence Astragalus increases energy by itself, the immune and anti-inflammatory benefits may reduce fatigue related to illness or overworked immunity. Any energy boost is likely an indirect result of immune system support rather than a direct energy-promoting effect.
2. Can Astragalus cure or treat cancer?
There is preliminary evidence certain Astragalus polysaccharides may help enhance immune cells’ ability to eliminate cancerous cells. However, evidence is still extremely limited. While some early lab and animal research is promising, no clinical trials support Astragalus as a cancer treatment yet. Much more research is needed before such claims can be made.
3. Can I take Astragalus long term?
There is no evidence suggesting long term Astragalus supplementation is harmful or dangerous when used appropriately. However, as with any herbal supplement, periodic breaks from usage is considered wise. Cycling on and off Astragalus every few months gives your body a break and may prevent dependence or tolerance issues developing over time.
4. Does Astragalus work right away?
Benefits tend to accumulate over weeks or months of consistent use rather than instantly. Subtle improvements in immunity may occur within 2-4 weeks but maximal benefits likely take at least a few months. Effects also diminish fairly rapidly after ceasing usage.
5. Can I take Astragalus while pregnant?
There is insufficient safety research regarding Astragalus usage during pregnancy so it is not currently recommended. Breastfeeding women should also avoid Astragalus supplements as a precaution until more data is available ensuring infant safety.
6. Will Astragalus interfere with my medication?
Astragalus is not known to negatively interact with most common medications but may potentially amplify immune system effects of immunosuppressants or blood thinning effects of anti-coagulant drugs. Anyone taking prescription medication should first consult their doctor before using herbal supplements like Astragalus.
As with any dietary supplements, ensure you carefully follow dosing directions, choose high quality products from reputable brands and consult your healthcare professional before commencing usage, especially if currently on other medications or have a medical condition.
With a long history of traditional use alongside modern clinical evidence backing up many proposed benefits, quality Astragalus supplements can be a safe and helpful addition to a healthy lifestyle for immune and whole body support.