Astragalus membranaceus is an important herb used in traditional Chinese medicine. It has been used in Chinese medicine for thousands of years, and is commonly used in combination with other Chinese herbs. In Chinese, Astragalus is known as Huang Qi (meaning yellow leader), because the root is yellow. It is a perennial plant that grows 16 to 36 inches tall, and is native to northern and eastern parts of China, Mongolia, and Korea. The Astragalus root is the medicinal part that is harvested.
In traditional Chinese medicine, Astragalus is commonly used as an energy tonic, to improve immune functions, for night sweats, to treat diarrhea, and prevent colds. In western herbal medicine, Astragalus is often used to enhance metabolism and digestion. It is also used to strengthen the immune system, and help the healing of wounds and injuries. Astragalus is also believed to help improve functions of the lung, adrenal glands and the gastrointestinal tract, increase metabolism, sweating, promote healing and reduce fatigue. [1]
Because Astragalus is such an important herb in traditional Chinese medicine, there is a large body of clinical studies done on this herb. Aside from the various health benefits already mentioned, Astragalus is also shown to have benefits in treating diabetes, speed up healing, has anti-tumor properties in the treatment of cancer, has anti-inflammatory properties, helps combat fatigue, stimulates the immune system and also has antioxidant properties, helps prevent bone loss, has anti-aging properties, and some studies have also found it to be generally safe without side effects.
Astragalus
Root and Cancer
Various studies have found Astragalus to have anti tumor properties making it a herb with cancer fighting potential. While there are numerous Astragalus studies showing its anti-cancer benefits, we have also found a limited number of contradicting studies. Generally, it appears Astragalus has a real and proven beneficial effect on colon cancer.
In a clinical trial conducted at the China Medical University in Shenyang, China, designed to determine the inhibitory effect of Astragalus on gastric cancer cells, human peritoneal mesothelial cell (cells that lines the body's serous cavity and internal organs) was co-incubated with gastric cancer cells and/or Astragalus. The results of this study found that Astragalus could partly suppress the apoptosis (programmed cell death) in the cells. They concluded that Astragalus inhibits apoptosis caused by the gastric cancer cells, and can be used in gastric cancer therapy. [2]
Astragalus membranaceus, a commonly used Chinese medicinal plant, has been shown to be capable of restoring the impaired T cell functions in cancer patients. Another study done at the Queen Elizabeth Hospital in Hong Kong studied the in vitro and in vivo anti-tumor effects of Astragalus. The researchers isolated 5 bioactive fractions from the root of Astragalus - one of the fractions was found to effectively suppress the in vivo growth of syngeneic tumor in mice, and could even partially restore the depressed mitogenic response in tumor-bearing mice. Their study demonstrated that Astragalus root could exhibit both in vitro and in vivo anti-tumor effects, which might be achieved through activating the anti-tumor immune mechanism of the host. [3] There are numerous studies which have similar findings; however, it is important to keep in perspective that Astraglus may not be effective in treat all types of cancer.
In a clinical trial performed at the Memorial Sloan-Kettering Cancer Center in New York, a commonly used Astragalus-based herbal formula (Jinfukang) previously found effective in non-small cell lung cancer (NSCLC) patients was tested. Patients with advanced NSCLC received the Astragalus formula for 3 weeks followed by 1 week of rest. 12 patients withdrew due to progression of the disease. This study was unable to determine any benefit of the astragalus herbal formula, and did not find it to affect patient survival. [4]
Astragalus Herb Remedies and Diabetes
Astragalus also plays a role in treating diabetes. Many research studies have found Astragalus to have therapeutic effects in treating diabetes, and many of these clinical trials involve human diabetic patients. One study investigated the effects of a traditional Chinese medicine, a prescription of Radix Astragali (Astragalus extract) and Rhizoma Ligustici Chuanxiong on treating type type 2 diabetic patients with microalbuminuria. 21 type 2 diabetic patients with microalbuminuria took part in this study. They were given the decoction of Radix Astragali and Rhizoma Ligustici Chuanxiong for a period of six months. At the end of the study, the researchers noted various improvements in the patients, concluding that the Astragalus medication may decrease urinary albumin excretion and improve endothelial dysfunction in type 2 diabetic patients with microalbuminuria. They believe that this is related with the anti-inflammation, anti-oxidation therapeutic effects of Astragalus. [5]
In another similar study investigating the effect of Astragalus and Panax notogingseng in treating type 2 diabetic patients with macroangiopathy, 94 patients were randomized into 2 groups treated either with Simvastatin or Astragalus and Ginseng. 40 healthy subjects were used as control. They found that after the treatment period, total cholesterol, LDL cholesterol, and VLDL cholesterol in the patients had improved. [6]
Other Astragalus Health Benefits & Research
Aside from having therapeutic applications for treating cancer and diabetes, Astragalus root also provides a host of other health benefits. It helps stimulate the immune system, and strengthens the body against diseases. It has anti-inflammatory and antioxidant properties helping to protect cells against free radicals. The root of Astragalus membranaceus is widely used in traditional Chinese medicine for tonifying the immune response and improving circulation. A recent Korean clinical trial reported that Astragalus root displays anti-inflammatory effects. [7] Another Chinese study investigated the scavenging effects of Astragalus. The results of their research showed that Astragalus could scavenge the active oxygen free radicals effectively. [8] Also in one of the above mentioned clinical studies of Astragalus root benefits for diabetes, that study cited the anti-inflammatory and anti-oxidation effects of Astragalus to benefit patients with type 2 diabetes. [5]
Astragalus root is widely used in traditional Chinese medicine to alleviate stress and stress related symptoms. It helps protect the body against various types of stress such as physical and emotional stress. There are numerous clinical studies that demonstrate the benefits of Astragalus root relating to various types of stress. A recent Korean study investigated the anti-fatigue effects of Myelophil, an extract of a mix of Astragali Radix and Salviae Radix, which has been used to treat patients with chronic fatigue. This was a randomised, double-blind, controlled clinical trial performed with 36 adults who complained of chronic fatigue. The subjects were divided among a control group and low- and high-dose groups (3 or 6g of oral Myelophil per day, respectively) and were monitored for 4 weeks. They found that taking 3g of the Astragalus mix (Myelophil) significantly decreased the fatigue severity score compared with the control group, suggesting that Astragalus (Myelophil) has a pharmacological effect against fatigue. [9]
Other studies involving mice have shown additional benefits of Astragalus root including anti-aging properties, and also helping to prevent bone loss. In a Korean study using rats as the test subjects, the research tested a drug candidate based on an herbal extract of Astragalus. Results of their research showed that the herbal extract inhibited tibia and lumbar bone loss. [10] In a Chinese study, the anti-aging effects of an Astragalus extract was tested to determine its effects on motor and memory in middle aged mice. Their research results found Astragalus lessened age-related alternations in both motor response and memory in the mice, and also enhanced the cellular immunity of the aged mice. [11] However, please keep in mind that these studies were performed using lab mice, and how applicable their results are to humans still requires further studies. But with the long list of Astragalus root health benefits we have outlined here, it's obvious why this herb has been such an important part of traditional Chinese medicine.
Astragalus Side Effects
There are few if any side effects of Astragalus. Of the many research and studies we reviewed and outlined here, none made any mention of reported side effects from the participants. Astragalus is generally believed to be safe and without any toxicity and side effects. One study using rats and dogs as test subjects, evaluated the toxicity and safety dosage range of Astragalus in clinical applications. The rats and dogs were administered an extract of Astragalus daily for 3 months. The study found Astragalus to be safe without any distinct toxicity and side effects. The safety dosage range is 5.7-39.9g/kg for rats and 2.85-19.95g/kg for beagle dogs. Obviously, these safe dosage ratings apply only to the tested animals, and do not necessarily reflect the safe dosage for humans. All in all, Astragalus appears to be safe with little to no side effects.
1. Wikipedia - http://en.wikipedia.org/wiki/Astragalus_membranaceus
2. World J Gastroenterol. 2009 Feb 7;15(5):570-7.
Astragalus extract inhibits destruction of gastric cancer cells to mesothelial cells by anti-apoptosis.
Na D, Liu FN, Miao ZF, Du ZM, Xu HM.
Department of Oncology, The First Affiliated Hospital, China Medical University, Shenyang 110001, Liaoning Province, China.
3. Cancer Lett. 2007 Jul 8;252(1):43-54. Epub 2007 Jan 16.
In vitro and in vivo anti-tumor effects of Astragalus membranaceus.
Cho WC, Leung KN.
Department of Clinical Oncology, Queen Elizabeth Hospital, Hong Kong SAR, People's Republic of China. chocs@ha.org.hk
4. Cancer Chemother Pharmacol. 2009 May 7. [Epub ahead of print]
Safety and pharmacokinetic trial of docetaxel plus an Astragalus-based herbal formula for non-small cell lung cancer patients.
Cassileth BR, Rizvi N, Deng G, Yeung KS, Vickers A, Guillen S, Woo D, Coleton M, Kris MG.
Integrative Medicine Service, Memorial Sloan-Kettering Cancer Center, 1429 First Avenue at 74th Street, New York, NY, 10021, USA, cassileth@mskcc.org.
5. Sichuan Da Xue Xue Bao Yi Xue Ban. 2005 Jul;36(4):529-32.
[The protective effects of Radix Astragali and Rhizoma Ligustici chuanxiong on endothelial dysfunction in type 2 diabetic patients with microalbuminuria]
Lu ZM, Yu YR, Tang H, Zhang XX.
Division of Endocrinology, West China Hospital, Sichuan University, Chengdu 610041, China.
6. Zhongguo Zhong Yao Za Zhi. 2004 Mar;29(3):264-6
[Effects of Astragalus and saponins of Panax notoginseng on MMP-9 in patients with type 2 diabetic macroangiopathy]
Liu KZ, Li JB, Lu HL, Wen JK, Han M.
Department of Endocrinology, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, China.
7. J Ethnopharmacol. 2008 Jan 17;115(2):184-93. Epub 2007 Oct 5.
Astragali Radix elicits anti-inflammation via activation of MKP-1, concomitant with attenuation of p38 and Erk.
Ryu M, Kim EH, Chun M, Kang S, Shim B, Yu YB, Jeong G, Lee JS.
Department of Biological Sciences, Ajou University, Republic of Korea.
8. Zhong Yao Cai. 1999 Jun;22(6):303-6.
[Scavenging effects of Astragalus and Gynostemma pentaphyllum with its product on O2-. and .OH]
Ma Z, Yang Z.
Graduate School, University of Science and Technology of China, Beijing 100039.
9. Complement Ther Med. 2009 Jun;17(3):141-6. Epub 2009 Jan 23.
Myelophil, an extract mix of Astragali Radix and Salviae Radix, ameliorates chronic fatigue: a randomised, double-blind, controlled pilot study.
Cho JH, Cho CK, Shin JW, Son JY, Kang W, Son CG.
East-West Cancer Center, Dunsan Oriental Hospital of Oriental Medical College of Daejeon University, Seo-gu, Daejeon, South Korea.
10. Arch Pharm Res. 2003 Nov;26(11):917-24.
Herbal extract prevents bone loss in ovariectomized rats.
Kim C, Ha H, Lee JH, Kim JS, Song K, Park SW.
Drug Research and Development Team, Korea Institute of Oriental Medicine, 129-11 Chungdam-dong, Kangnam-ku, Seoul 135-100, Korea. cskim@kiom.re.kr
11. Acta Pharmacol Sin. 2003 Mar;24(3):230-4.
Anti-aging effect of astragalosides and its mechanism of action.
Lei H, Wang B, Li WP, Yang Y, Zhou AW, Chen MZ.
Institute of Clinical Pharmacology, Anhui Medical University, Hefei 230032, China. keerfood@mail.hf.ah.cn
12. J Ethnopharmacol. 2007 Mar 21;110(2):352-5. Epub 2006 Sep 27.
Subchronic toxicity studies of Radix Astragali extract in rats and dogs.
Yu SY, Ouyang HT, Yang JY, Huang XL, Yang T, Duan JP, Cheng JP, Chen YX, Yang YJ, Qiong P.
School of Biosciences and Technologies of Central South University, 172 Tongzipo Road, Changsha 410013, China.
