Every year as winter rolls around, we fear the cold or flu that will knock us off our feet for a week. The winter season brings with it a wide array of cold and flu viruses that make their rounds across America.
Approximately 62 million Americans will miss work due to a flu-related illness this coming season.
In “The Flu Vaccine: What You Need to Know,” I talked about natural prevention strategies for the flu that include vitamin D, elderberry and zinc. These should be part of your medicine toolkit to help ward off colds and flu.
To winterize your immune system, use these super-immunity herbs and mushrooms:
Astragalus is my number one favorite winter immune tonic. A plant with long stems and purple flowers, the astragalus is harvested for its roots. Within these roots are astragalosides, plant constituents that stimulate the immune system.
Astragalus also contains other immunostimulants, such as polysaccharides, beta-sitosterols, and plant flavonoids. Paolysaccharides increase immune-mediated anti-tumor activity.
The dried root may be added to soup or decoction, which is an infusion made by boiling the roots. It may also be taken in a capsule or extract.
Take 250 mg daily or drink a decoction of the powdered root several times a week to keep your immune system strong during cold and flu season.
Beta-glucans are chains of glucose molecules attached end-to-end, with branching side chains being the most immunologically active. Molecular chemistry aside, beta glucans are powerful “biological response modifiers” able to activate our innate immune system. 
Several studies have shown the benefits of beta-glucans in reducing the risk of serious post-operative infections in high-risk surgical patients.  
Another study found that mice given yeast Beta-glucan with or without antibiotics were protected against anthrax infection.
Most studies used 1,3 beta-glucan sourced from the Saccharomyces cerevisiae yeast. You can also find this powerful immune system booster in several mushrooms used in every day cooking, such as Reishi, Shiitake and Maitake.
At the first signs of a cold, start taking 100mg of beta-1,3/1,6–D–glucan, three times a day. Another option, make super-immunity soup such as the one included here, adding mushrooms that contain 1,3/1,6 beta-glucan. Sip throughout the day.
The use of Cordyceps dates back to traditional Tibetan and Chinese medicines. Cordyceps is known in Chinese medicine as a powerful lung tonic.
It fortifies the Qi circulation in the lungs and is especially useful for someone who is prone to bronchitis, wheezing or coughing. Cordyceps has been shown to increase respiratory capacity.
Like other tonic mushrooms, it contains polysaccharides that have a fortifying effect on the immune system. 
Take 1000 mg capsules twice a day as a means to strengthen your defenses. Cordyceps may also be prepared as a decoction by adding to boiling water, then simmering for 10 to 15 minutes.
1 yellow onion
2 large organic carrots
2 stalks of organic celery
1 head of kale
30g dried or fresh shiitake mushrooms
30g dried astragalus root
1-2 tbsp chopped ginger
10 garlic cloves
1 bunch of cilantro
¼ cup olive oil
Ground black pepper
Wash and cut the vegetables. You may sauté the vegetables in a little sesame or olive oil, for extra browning and flavor. Wash mushrooms and astragalus root and place them into a medium saucepan. Add cold water and bring to a boil. Lower the heat, and cook uncovered for 40 minutes. Add sea salt and black pepper to taste.
Vincent Pedre, M.D. is an integrative, Holistic General Practitioner and Board-Certified Internist in private practice in New York City. Follow Dr. Pedre on Facebook and Twitter.
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