Mushrooms have been used medicinally for thousands of years.¹

Modern science has pinpointed a primary reason:

They contain beneficial compounds called beta glucans that boost immune function.^2-5

On their own, beta glucans deliver antiviral and immunity-strengthening properties.^2-5

In human studies, taking beta glucans reduces the length and severity of upper respiratory tract infections such as the common cold and flu.^6-11

Combining beta glucans with medicinal mushrooms may supercharge a variety of immune functions.

What Are Beta Glucans?

Beta glucans are a group of polysaccharides found in the cell walls of mushrooms, seaweed, and whole grains.⁷

Beta glucans derived from yeast and fungi are known for their immunomodulating properties.⁷

They also help nourish the gut microbiota and augment the action of immune cells.^3,12-15

Key Immune-Supportive Mushrooms

There are hundreds of strains of mushrooms. Three that most effectively support the immune system are shiitake, maitake, and chaga.

Shiitake

Shiitake mushrooms have long been used in traditional Asian medicine.¹⁶ They increase the number of immune cells, including T-cells, which fight specific kinds of viruses, and NK (natural killer) cells, which kill a variety of virally infected cells and tumors.¹⁷

In cell studies shiitake extract was able to directly inactivate several types of viruses and block viral replication.^18-20

In an animal model of severe bacterial lung infection, shiitake mushrooms significantly decreased the number of bacteria in the lungs and improved the animals’ condition.²¹

Shiitake also boosts secretion of antibodies that protect the digestive tract and reduces C-reactive protein, a marker of inflammation.¹⁷

Maitake

Commonly used in cuisine, maitake mushrooms were shown in preclinical studies to activate some of the first immune cells to fight an infection, including NK cells and macrophages.^22,23

Extracts of maitake also induce the secretion of interferons, proteins that improve the body’s ability to defend against infection.²³

Chaga

Chaga mushrooms, which grow on alder, beech, birch, and various other hardwood trees, are powerful immuno-modulators.

When scientists treated mice with a drug that inhibits immune system activity, chaga extract returned levels of immune cells almost back to normal. It also kept down levels of tumor necrosis factor, a marker of inflammation.²⁴

In preclinical studies, chaga demonstrated antiviral activity against a wide range of viruses, including influenza, herpes, hepatitis C, HIV, and others.²⁵

Activating the Immune System

Mushrooms contain numerous health-promoting compounds. But perhaps the most powerful and bioactive immune supporters are beta glucans.

Beta glucans bind to receptors found on an assortment of cells important for immunity.^3,26 This boosts the function of these cells, helping them defend against infection and other threats.

Immune responses can be divided into two types:²⁷

• Innate immunity, which forms the body’s first line of defense, is accomplished by immune cells including macrophages, neutrophils, and NK cells.
• Adaptive immunity cells include lymphocytes, such as B-cells and T-cells. These are the specialists brought in later to fight off specific threats, like a particular bacteria or virus. Adaptive immunity helps the body develop long-term immunity to a pathogen.

Beta glucans activate and stimulate both systems.^3,4,17,28,29

Results of Human Tests

To validate these benefits in humans, scientists conducted a number of different trials. Volunteers were randomized to receive either a placebo or beta glucans. Most of these studies used a 250 mg dose of beta-glucans.^6-11

Beta glucans demonstrated infection-fighting effects, particularly in upper respiratory tract infections such as the common cold and flu.

Participants who received beta glucans had:^6-11

• Fewer symptomatic days,
• Less severe infection symptoms,
• Fewer workdays lost to illness,
• Increased numbers of immune cells in the blood,
• Higher levels of interferon secretion, and
• Increased secretion of antibodies in the saliva, a defense against digestive tract and respiratory tract infections.

Beta glucans can improve immune responses to other challenges as well. One study looked at ragweed allergy sufferers who received either a placebo or 250 mg of beta glucans.³⁰

After four weeks, those receiving beta glucans had significant reductions in total allergy symptoms and severity. Measures of mood, energy, vigor, sleep, and overall quality of life were all improved.³⁰

Reversing Immune Senescence

The elderly become more susceptible to infectious diseases and cancer due to a deterioration of immune function known as immunosenescence.³¹

In animal models of aging, intake of beta glucans can help prevent or even reverse this weakening of the immune system.^28,32

In one mouse study, beta glucans boosted the numbers of immune cells, and improved their function, which had a rejuvenating effect on immune system responses.³²

Stronger Gut Defenses

The gut microbiota is made up of the trillions of microorganisms in the digestive tract. Beneficial populations of these microorganisms are critical to fighting infections and maintaining optimal overall health.

Both mushrooms and isolated beta glucans encourage the growth of healthy microbiota.^3,13-15

The benefits don’t stop there. When beneficial bacteria consume beta glucans, they produce short-chain fatty acids as a byproduct.^13,15 Among other benefits, these fatty acids:³³

• Reduce harmful inflammation,
• Support a healthy gut lining,
• Defend against cancer, and
• Help regulate appetite and metabolism.

Combining beta glucans with immune-supporting mushrooms may help maximize the function of the immune system.

Summary

Mushrooms have wide-ranging medicinal properties, including powerful support for the function of the immune system.

Beta glucans are compounds found in the cell walls of mushrooms, and in yeast, seaweed, and some grains that are also known to help the immune system.

Beta-glucans have been shown to improve immune responses, helping to:

• Prevent and fight infections like the common cold and flu,
• Prevent or reverse immune senescence, and
• Support a healthy gut microbiota.

A carefully formulated blend of beta glucans from yeast as well as shiitake, maitake, and chaga mushrooms can help support healthy immune function.

If you have any questions on the scientific content of this article, please call a Life Extension Wellness Specialist at 1-866-864-3027.

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