(NaturalNews) There are numerous herbs which are known, both through traditional knowledge and modern scientific research, to benefit the immune system. Typically, such herbs work by directly attacking and destroying disease-causing pathogens, increasing the numbers and/or activity of immune cells in the body, or both. Here are some powerful immune-boosting herbs, in no particular order.

1.Astragalus

Astragalus was described by Mark Stengler, ND, as "one of the best herbs in the world for enhancing the protective effects of the immune system." This herb boosts immunity by increasing the numbers and/or enhancing the function of various immune cells in the body, including macrophages, natural killer cells, white blood cells and antibodies. It also stimulates the production of interferon, a potent antiviral compound. In Traditional Chinese Medicine, where astragalus is also known as Huang Qi, it is used to help prevent common colds and upper respiratory tract infections.

2.Echinacea

Echinacea gives the immune system a boost by stimulating the immune cells that patrol the body and fight off disease-causing pathogens. This herb raises both the number and activity of white blood cells, a core component of the body's immune system, and activates interferons, which are required for protective immune defense against pathogens such as viruses, bacteria, parasites and tumor cells. Echinacea also contains other chemicals which prevent the spread of bacteria and viruses, and has even been shown to have anticarcinogenic properties.

One particular study in Germany found that 30 drops of Echinacea taken thrice daily helped to enhance the activity of phagocytes, a type of immune cell, in the body by 120% after 5 days of consumption.

The direct antiviral properties of Echinacea make it valuable considering the limits of conventional medicine in dealing with viral infections.

3.Licorice

There are two compounds in licorice, glycyrrhizin and glycyrrhetinic acid, which research has shown to elevate the levels of interferon in the body. This helps to keep the replication of viruses and other pathogens in check. Licorice root is actually found in many Chinese, Ayurvedic, Japanese and even Western formulas for treating infections and infectious diseases.

In Europe, physicians have a high regard for licorice root as one of the best herbal treatments for fighting viral hepatitis. Both hepatitis B and hepatitis C are treated intravenously using licorice in Europe.

4.Mushrooms

Medicinal mushrooms, including shiitake, reishi and maitake, contain compounds which ramp up the immune system and enhance the body's ability to fight diseases and infections. Shiitake and in particular maitake have also been shown to have anticancer properties.

5.Goldenseal

Goldenseal has been found in research to have antiviral and antibacterial properties, as well as the ability to both increase immune cell production and enhance immune cell activity.

6.Onions

Onions help to protect the body against fungal, bacterial and worm infections. It can be used in a broth or soup to help combat sore throats and upper respiratory tract infections.

7.Garlic

Garlic also contains compounds which fight and destroy bacteria, viruses, fungi, parasites and even cancer cells. For the best effect, fresh garlic should be chopped or crushed, left for 10-15 minutes, and then eaten raw.

8.Ginseng

Research in Germany found that Siberian ginseng boosts immunity. In particular, the activity of lymphocytes are enhanced, which are immune cells in the body which fight infection. In addition, Chinese ginseng has also been found to give immune function a boost.

9.Cordyceps

Cordyceps has been found in both human and animal studies to have immunity-boosting properties.

10.Green tea

Research carried out on animals has revealed that green tea helped enhance the production of immune cells in the body.

11.Spirulina

Spirulina has been shown to help stimulate various aspects of the immune system. Certain spirulina extracts have also displayed powerful antiviral properties.

Sources for this article include:

Stengler, Mark, ND. The Natural Physician's Healing Therapies: Proven Remedies Medical Doctors Don't Know. New York, NY: Prentice Hall Press, 2010. Print.

Murray, Michael, ND., Pizzorno, Joseph, ND., and Pizzorno, Lara, MA, LMT. The Encyclopedia of Healing Foods. New York, NY: Atria Books, 2005. Print.

Gaby, Alan R., MD. The Natural Pharmacy: Complete A-Z Reference to Natural Treatments for Common Health Conditions. 3rd ed. New York, NY: Three Rivers Press, 2006. Print.

Haas, Elson M., MD, and Levin, Buck, PhD, RD. Staying Healthy With Nutrition: The Complete Guide to Diet and Nutritional Medicine. New York, NY: Celestial Arts, 2006. Print.

About the author:
Reuben Chow has a keen interest in natural health and healing as well as personal growth.

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