Astragalus root is commonly used as an herbal remedy in China, Mongolia and other Asian countries. The roots of the astragalus plant are dried and aged for at least three years before they are used to prepare extracts, powdered capsules and medicinal teas. Historically, astragalus was used to promote longevity and speed recovery from illnesses, although it’s now viewed as an immune system booster, antioxidant and mild antimicrobial.
Astragalus root may boost the immune system in multiple ways, according to the University of Maryland Medical Center. The evidence suggests that astragalus extract contains compounds, such as polysaccharides, which stimulate specialized immunity cells called natural killer cells, monocytes and lymphocytes. This root may trigger the release of strong antiviral and anticancer substances named interleukin-2 and interferon, although the U.S. Food and Drug Administration stresses that more research is needed before any medical claims can be made. Other compounds in astragalus root called saponins display mild antiseptic properties especially against pathogenic bacteria, helping to prevent the immune system from being overworked.
Antioxidants are beneficial to health because they eliminate or neutralize free radicals, which are end products of oxidation that harm a variety of tissues, especially the insides of arteries. The saponins, flavonoids and triterpenes in astragalus root extract are strong antioxidants and may help to slow the deterioration of tissues, which is the primary cause of aging and a significant cause of many degenerative diseases such as arthritis, kidney failure and congestive heart failure.
Astragalus root is also classified as an adaptogen, which means it helps the body resist the harmful effect of stress and fatigue by stimulating the production and secretion of cortisol from the adrenal glands and by balancing other endocrine hormones. It may help to keep you from feeling rundown, although you shouldn't rely on it solely for this purpose. Adaptogens, which also include ginseng root and licorice root, may also enhance libido and give you an extra boost while working out.
Anti-aging potential has been the claim to fame of astragalus for centuries, and there now seems to be some biochemical understanding of how it may contribute to well-being and longevity. Compounds in the roots called astragalosides and cycloastragenols activate telomerase enzymes, which help to prevent the protective ends of chromosomes, called telomeres, from degrading. The degradation of telomeres negatively affects cell division and contributes to tissue aging. Astragalus protects the telomeres from degradation and may also stimulate telomere renewal. Although intriguing, much more human research is needed before astragalus can be touted as a fountain of youth.
Some adaptogens are recommended only for short-term use, but astragalus is commonly recommended for many months at a time by practitioners of traditional Chinese medicine. Typical dosages of astragalus root extract range from 200 up to 500 milligrams three times a day, but consult with a health professional familiar with herbal remedies before starting supplementation.
- University of Maryland Medical Center: Astragalus
- Chinese Herbal Medicine: Materia Medica; Dan Bensky et al.
- Principles and Practice of Phytotherapy: Modern Herbal Medicine; Simon Mills and Kerry Bone
- Natural Standard Herb & Supplement Reference: Evidence-based Clinical Reviews; Catherine E. Ulbricht and Ethan M. Basch
Sirah Dubois is currently a PhD student in food science after having completed her master's degree in nutrition at the University of Alberta. She has worked in private practice as a dietitian in Edmonton, Canada and her nutrition-related articles have appeared in The Edmonton Journal newspaper.